i— · [ p r o c . r o y . s o c . v i c t o r i a , 5 7 (n .s .j, p t s .]> ii., 1945.] a r t...

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[Proc. Roy. Soc. V ictoria, 57 (N.S.j, Pts. ]>II., 1945.] A r t V I.— Chonetidae from the Palaeozoic Rocks of Victoria and their Stratigraphical Significance. By EDMUND D. GILL, B.A., B.D. [Read 14th December, 1944; issued separately 10th December, 1945.] Summary. A survey is made of all the known Chonetidae from the Palaeozoic rocks of Victoria. Comments are made on species of Chonetes and Anopha already described, and the following new species are erected — Chonetes bowieae C proiluctoida, C. killarevsis , C. psiloplia, C. ruddorkensis, C. taggertyensis, aiul C. gaskini. The affinities of these forms with those found elsewhere are given, and their stratigraphical significance commented upon. A sub- division of the Yeringian Series is proposed. Introduction. Fossils of the brachiopod family Chonetidae (the classification of the Fossilium Catalogus is adopted) are known in Victoria only from Silurian and Devonian rocks, and they belong to the two genera Chonetes (sensu stricto') and Anoplia. The following table summarizes, our knowledge of the occurrence of this group:— Series. Buchan Beds Bindi Beds . . Yeringian Melbournian Age. M iddle Devonian M iddle Devonian Lower Devonian part at least) (in Lower Ludlow (in part at least) Genus and Species. Chonetes australis McCoy C. australis McCoy C. gaskini, sp nov. C. bowieae. sp. nov. C. cresswelli Chapman C. killarensis, sp. nov. C. productoida, sp nov. C. psiloplia sp. nov.- C. robusta Chapman C. ruddockensis , sp. nov. C. taggertyensis, sp. nov. Anopha australis G ill A. withersi G ill Chonetes melbournensis Chapman The Devonian genera Eodevonaria and Chonostrophia have not been found in Victoria. Fig. 1 attempts to represent diagram- matically the relationships of the various genera of the family Chonetidae, and of that family to the closely-related family Productidae.

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Page 1: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

[ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S . j , P t s . ] > I I . , 1945.]

A r t V I . — C honetidae f r o m the P a laeozo ic R o c k s o f V ic to r ia a nd

th e ir S tra t ig ra p h ica l S ign ifica n ce .

B y E D M U N D D . G IL L , B .A ., B .D .

[ R e a d 1 4 th D e c e m b e r , 1 944 ; is s u e d s e p a ra te ly 1 0 th D e c e m b er , 1945.]

S u m m a r y .

A su rv e y is m a d e o f a l l th e k n o w n C h o n e tid a e f r o m th e P a la e o z o ic ro c k s o f V ic to r ia . C o m m e n ts a re m a d e o n sp e c ie s o f C h o n e te s a n d A n o p h a a l r e a d y d e s c r ib e d , a n d th e f o l lo w in g n e w sp e c ie s a re e re c te d— C h o n e te s b o w ie a e C p ro i lu c to id a , C . k i l l a r e v s is, C . p s i lo p lia , C . r u d d o r k e n s is , C . ta g g e r ty e n s is , a iu l C . g a s k in i . T h e a f f in i t ie s o f th e s e f o r m s w i th th o s e fo u n d e lse w h e re a re g iv e n , a n d t h e i r s t r a t ig r a p h ic a l s ig n i f ic a n c e co m m e n te d u p o n . A s u b ­

d iv is io n o f t h e Y e r in g ia n S e r ie s is p ro p o se d .

I n t r o d u c t i o n .

F ossils o f the b rach iopod fam ily C ho netidae ( th e c lassif ication o f th e F o ss i l iu m C a ta logus is ad o p ted ) a re k n o w n in V ic to r ia on ly f ro m S ilu r ia n an d D evon ian rocks, and th ey belong to the tw o g en e ra C ho n etes ( se n su str ic to ') an d A n o p lia . T h e fo llow ing tab le sum m arizes, o u r kno w led ge o f th e o ccu rrence of th is

g ro u p :—

S e r ie s .

B u c h a n B e d s

B in d i B e d s . .

Y e r in g i a n

M e lb o u r n ia n

A g e .

M id d le D e v o n ia n

M id d le D e v o n ia n

L o w e r D e v o n ia n p a r t a t l e a s t )

( in

L o w e r L u d lo w ( i n p a r t a t le a s t )

G e n u s a n d S p e c ie s .

C h o n e te s a u s t r a l i s M c C o y

C . a u s t r a l i s M c C o y C . g a s k in i , s p n o v .

C . b o w ie a e . sp . n o v .C . c r e s s w e l l i C h a p m a n C . k i l l a r e n s is , s p . n o v .C . p r o d u c to id a , s p n o v .C . p s i lo p l ia sp . nov .- C . r o b u s ta C h a p m a n C . r u d d o c k e n s i s, s p . n o v .C . ta g g e r t y e n s i s , s p . n o v .A n o p h a a u s t r a l i s G il l A . w i t h e r s i G i l l

C h o n e te s m e lb o u r n e n s i s C h a p m a n

T h e D ev o n ian g en era E o d ev o n a r ia an d C h o n o stro p h ia h ave n o t been fo u n d in V ic to r ia . F ig . 1 a ttem p ts to re p resent d iag ram - m atica lly th e re la tio n sh ip s o f th e v a r io u s g en e ra of th e fam ily C honetidae, an d o f th a t fam ily to the c losely -re la ted fam ily

P ro d u c tid ae .

Page 2: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

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Page 3: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

C h onetidae f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 127

D i s c u s s i o n o f t h e G e n u s C h o n e t e s .

Class B R A C H IOP O D A D um eril.

F am ily C H O N ET ID A E H a ll a n d C larke, 1895.

G enus C h o n e t e s F isc h e r de W aldhe im , 1837.

G e n o l e c t o t y p e C h o n e te s sp . F is c h e r = C . v a r io la ta D O rb ig n y , 1842, a s in te rp re te d b y D e K o n in c k , 1847 (q u o te d f r o m b o ss il iu T H

C a ta lo g u s ) .

E t y m o l o g y o f G e n e r i c N a m e .— T h e nam e of th e genus is d e r iv ed f ro m the fem in in e G reek no u n “ chone,” a funn e l, b u t the fo rm “ chonetes ” is m ascu line, an d so s tr ic t ly speak ing a ll the tr iv ia l nam es sh ou ld be m ascu line in ag reem en t. S u ch they w ere m ad e by m any ea rly w r ite rs , b u t fem in ine fo rm s have been estab lished by co n sis ten t recen t usage, an d it w ou ld be co n fu s in g now to change all th e nam es.

D i a g n o s i s o f t h e G e n u s .

In equ iva lv e , eq u ila te ra l chonetids, w ith a s tra ig h t h inge-line, a n d a row o f ho llow sp ines a long th e v en tra l ca rd ina l m arg in . V e n tra l v a lve c o n v e x ; do rsa l va lve f la t to concave. In te r io r v en tra l va lve w ith tw o sm all tee th , u n su p p o rted by d en ta l lam ellae. C a rd in a l a rea n a rro w and sm ooth . P ed ic le obso lescent as show n by c losu re o f ped ic le open ing by a pseu do -de ltid ium. M uscle im p ress io n s h o n -d e n d r it ic . S u rfa c e usua lly covered w ith ra d ia tin g s tr iae o r r ib s ; ra re ly sm ooth . In ter io r, o f shells com m only pap illose in th e pa llia l reg ion .

P h y l o g e n e t i c s.

T h e genus C ho n etes is a s im p le exp ress io n o f th e fo rm s p rev iou s ly g ro u p ed in th e la rg e fam ily P ro d u c tid ae . I t is th e stock f ro m w h ich th e U p p e r P alaeozo ic p ro d u ctid s w ere evo lved . C h o n etes ap p eared in th e la te O rd o v ic ian w hereas P ro d u c te lla d id n o t ap p ear ti l l th e D evon ian . T h e genera C h o n etes, P ro d u c te lla , an d P ro d u c tu s a re v ery s im ila r, d iffe ring charac te ris tica lly , in th e ir d eg ree o f sp inosity . Th e sp ines w ere p rob ab ly a m eans o f a tta c h m e n t com p en sa tin g fo r , a defic ient o r obso lescent ped ic le (B ee ch er, 1898, p. 3 5 1 ). T h ey m ay be re g a rd e d as a m ark o f g ro u p geron tism . In h is d iagnosis o f the genus C h o n etes, S ch u ch e rt w r ites o f th e sp ines (1913, p. 3 8 9 ), “ T h ese a re p ro lon g atio ns o f tu b es w h ich p e n e tra te ob liquely th e substance o f th e -sh e ll a lon g th e h ing e-lin e .” P rac tic a l ly all the V ic to r ia n species h av e th e ir sp ines a t r ig h t ang les to th e h inge- line, an d in a n u mb e r o f cases it is k n o w n defin ite ly th a t the tu bes p en e tra ted th e shell su bstan ce a t r ig h t ang les a n d n o t ob liquely . A n u m b er o f species h av e been no ted bo th in E u ro p e an (e .g ., C. m a rg a r ita cea ) an d A m er ican (e .g ., C. se tig era ) deposits w h ich h av e th e ir sp ines set a t r ig h t ang les to th e

h inge-line.

Page 4: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

128 E d mu n d D . G ill:

O n e v isua lizes th e C h onetidae a r is in g f ro m S tro p h o men id s o f th e type o f C h o n eto id ea an d S o w erb ye lla , w h ich a re qu ite choneto id in s tru c tu re b u t lack sp ines. E o c h o n e te s (R eed , 1917) is a p lec tam bon itin w ith sp ines. B reg e r (1 9 0 6 ) erected the su b ­g enus E o d ev o n a r ia to accom m odate th e den ticu la te fo rm s o f C honetes. D e n ticu la tio n is so im p o rtan t a fe a tu re phy logenetica lly th a t S ch u ch e rt an d L e V ene (1 9 2 9 ) ju s tif iab ly acco rded E o d ev o n a r ia g en eric s ta tu s.

S p ines a re th e p rin c ip a l g eneric fe a tu re o f C honetes, a n d a re also o f considerab le v a lue fo r specific d e te rm in a tio n . H a ll (1 8 9 2 ) w rites, “ T h e ir co m p ara tive s tre n g th o r d irec tio n of ten fu rn ish e s m eans, fo r 's p e c i f ic d e te rm in a tio n , b u t I h av e no t been ab le to sa tis fy m y se lf th a t th e n u m b er o f sp ines on th e h inge-line is o f specif ic im p o rtan ce .” T h e in v estig a tio n o f th e V ic to r ia n fo rm s suggests th a t th e n u m b er o f sp ines is co n stan t in a species. A s H a ll says, th e n a tu re o f th e sp ines is o f specif ic im p ortance . F o r in stan ce C. ro b u s ta an d C. k i l la ren s is hav e a so m ew h at s im ila r o u tline an d o rn am en t, an d b o th possess a m ed ian su lcus, b u t the sp ines o f each species a re v e ry d iffe ren t. In C. ro b u s ta th ey a re long, th ick , an d s tra ig h t, w hereas in C. k il la ren s is th ey a re sh o rt, thin,_ an d sinuous. E v id en tly th e re w as ra p id v a r iat io n in th is spec ia lization o f th e genus.

C l a s s i f i c a t i o n . -

D e K o n inck (1 8 4 7 ) . classified C h o n etes in h is m o n og rap h acco rd in g to th e su r fa c e o rn a m e n t, as fo l lo w s :—

A s u r f a c e o rn e e d e p l is c o n c e n tr iq u e s . 1. C o n c e n tric a e .p lu s d e 100 c o te s l is se s . . 2. C o m a ta e .m o in s d e 100 m a is p lu s d e 30 c o te s l is se s 3., S t r iata e .d e . m o in s d e 30 c o te s l is se s . . . 4. P l ic o sa e .d e c o te s ru g u e u s e s . . . . . . 5. R u g o s a e .

I n th e ligh t o f la te r s tu d ies su ch a c lassif ication ap p ears ra th e r a rb it ra ry an d n o t based on gen e tic re la tio n sh ip s, b u t P aecke lm ann (1 9 3 0 ) h as c rea ted su b -g en era based on these d iv is ions. A ll the V ic to r ia n fo rm s com e w ith in th e class S tr ia ta e o f De K on inck , i.e., th e C h o n e tes se n su s tr ic to o f P aecke lm ann .

G rab au an d S h im er (1 9 0 9 ) h ave classified C ho n etes acco rd in g to th e p resence o r absence o f o rn am en t, an d the p resence o r absence o f a su lcus, as fo l lo w s :—

A . C h o n e te s w i th r a d ia t in g s t r ia e .

( a ) V e n t r a l v a lv e w i th a m e d ia n su lc u s .

( b ) V e n t r a l v a lv e w i th o u t a m e d ia n su lc u s .

B . S m o o th C h o n e te s .

G ro up A is fu r th e r sub -d iv id ed by G rab au an d S h im er acco rd in g to 'th e n u m b er o f sp ines, ca rr ie d on th e ven tra l ca rd ina l m arg in . ■ A ll th e species described in th is p ap e r com e w ith in G rou p A . C. cressw e lli, C. ro b u sta , an d C. k i l la ren s is com e w ith in th e sub -sec tion “ a ,” an d th e re s t o f th e species in sub -sec tion “ b .”

Page 5: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

P re n d e rg a s t (1 9 4 4 ) has recen tly d ism issed S ch u ch e rt ’s 1913 c lassification o f p ro d u c tid s based on m eans o f a ttach m en t as- “ p u re ly a rb i t ra ry ,” a rg u in g th a t it “ m akes no a llow ance fo r a s im ila r ity o f ex te rn a l fo rm d u e to g ro w th u n d e r s imila r en v iro n ­m enta l cond itions ” (p . 1 0 ). T h is v iew is ex p ressed m o re 'specifically in th e s ta tem en t th a t “ G iven th e co nd ition necessary fo r sp ine deve lopm ent, th a t is, a p len tifu l su pp ly o f C a C 0 3, any species w ill p rob ab ly develop sp ines in th e sam e p osition in all its m em bers. T h e inc lin a tion o f th e sp ines to th e body su rface w ill depend u pon th e h a rd n ess o f th e sea-floor, a r is in g a t a h igh ang le w here th e su b s tra tu m is so f t an d being ad h e ren t w here it is h a rd . In m o d e rn lam ellib ranchs th e te m p e ra tu re o f the w a te r has a m ark ed effect on th e th ickness o f the shell, th e A rc tic fo rm s hav in g a th ick shell an d th e w a rm w a te r fo rm s o f th e sam e species a shell th in a lm o st to f rag ili ty . T h e d if fe ren ce betw een th e I rw in fo rm s, th in w ith sh o rt sp ines o f sm all b o re an d tho se f ro m M t. M arm io n , th ick -sh e lled w ith heavy spines, o f T a en io th a e ru s su b q u a d ra tu s (M o r r is ) is possib ly due to th e d iffe rence in te m p e ra tu re o f th e sea a t th e tw o loca lities.”

F ro m a co n s id e ra tio n o f P re n d e rg a s t ’s s ta tem en ts, the fo llow ing po in ts em erge :—

(1 ) S ch u ch e rt ’s 1913 c lassif ication is cha llenged but n o ­m en tio n m ade o f h is 1929 rev ised c lassif ication in th e F o ss i l iu m C ata logus.

(2 ) P h en o typ es re su lt , f ro m in te ra c tio n betw een genetic con­sti tu t io n and env iron m en t. Im ag ine, fo r instance, a C honetes' in d iv id u a l .w ith genes fo r sp ines o f a ce rta in size an d shape, o r ien ta te d to the shell in a ce rta in w ay. T h a t such genes ex is ted m ay be ju s t ly in fe r re d f ro m th e fa c t th a t sp ines o f a certain , ch a ra c te r a re a lw ays fo u n d on in d iv id ua ls o f th e sam e species. I f th e op tim um am o u n t o f ca lc ium sa lts (o r the ab ility to assim ila te th e m ) fo r b u ild ing such sp ines in such a w ay is n o t p resen t, th en sp ines w ill deve lop , b u t no t o f the stre n g th th a t w ou ld o th erw ise be a tta in ed . T h e w ho le exoske le ton w ill show signs o f ca lc ium sta rv a tio n . P au c ity o r p len ty o f ca lc ium salts

. w ill n o t de te rm in e th e absence o r th e p resence o f sp ines, b u t th e ir deg ree o f deve lopm ent. I f ca lc ium sa lts w ere absen t a ltogether,, th e re w ou ld be no exo sk e le ton an d no shellfish. I f th e calciunT. supp ly is low , th e n th e w ho le ex oske le ton w ill su ffe r by th e shell’ be ing th in a n d th e sp ines w eak. T h is is w h e re P re n d e rg a s t ’s a rg u m e n t breaks dow n. H o w e v er ab n o rm a l th e cond itions be, the m eans o f a ttach m en t o f th e shell, v iz., th e sp ines, w ill be p resen t, an d so av a ilab le as an o b jec tive m eans fo r th e classifica­tion o f species, g enera , &c.

(3 ) T h e m eans o f a ttac h m e n t re p re se n t a line o f rapid •evo lu tion fo r th e g ro u p u n d e r d iscussion . A p r io r i, such lines o f rap id evo lu tion shou ld co n stitu te good bases fo r c lassification . T h e w ide v a r ie ty in th e n a tu re o f th e sp ines in the num erous-

C h onetidae f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 129*

Page 6: I— · [ P r o c . R o y . S o c . V i c t o r i a , 5 7 (N .S .j, P t s .]> II., 1945.] A r t V I . — Chonetidae fro m the Palaeozoic R ocks o f V ictoria an d their Stratigraphical

130 E d mu n d D . G ill:

species o f C h o n e tes ind ica tes th a t th e re m u s t h av e been a h igh m u ta tio n ra te o p era ting . T h e sp ines on th e ex o sk e letons o f som e m o d ern shells seem to h ave no b io log ical sign ificance. T h ey m ay be m u ta tio n s w h ich rem a in because th ey a re n e ith e r an ad v an tage n o r a d isad v an tag e to th e an im al. H o w ev er, th e sp ines o f th e C h o n e te s-P ro d u c tu s series ap p e a r to have p layed an im p o rtan t p a r t by keep in g th e an im al above th e m u d d y sea-f loor w here th e w a te r w o u ld be c lea re r a n d th e supp ly o f foo d m o re certa in . T h e g ro u p w as a v e ry successfu l one, m a in ta in in g itse lf o v er a v as t s tre tc h o f tim e, an d e x is t in g in p ro lif ic num bers; T h e sp in o s ity o f th ese fo rm s w as ap p a ren tly a n im p o rta nt b io log ical fe a tu re . T h e series ended u p w ith th e R ich th o fen iidae , w h ich lost th e pow er to e leva te them selves by sp ines a n d e leva ted them ­selves above th e sea-floor by th ick en in g th e v en tral valve u n til th e y looked like cy a th o ph y llo id corals.

(4 ) P re n d e rg a s t ’s re fe re n c e to fo rm s lack in g ca lc ium because in w a rm tro p ica l seas is n o t easy to fo llow . C ora l re e fs a re trem en d o u s accre tio ns o f ca lc ium , an d such shells as th e b ig clam s in d ica te the w ith d raw a l f ro m tro p ica l and su b -tro p ica l seas o f v e ry la rg e am o u n ts o f lim e. T h e b iggest an d m ost extra v ag an tly •o rnam ented shells com e f ro m tro p ica l seas. M an y exten s iv e beds -of l im estone hav e been la id do w n in tro p ica l w a te rs . T h ese fac ts do no t suggest pauc ity o f ca lc ium in tro p ica l w a te rs , o r lack o f ab ility on th e p a r t o f m arin e o rg an ism s in th ose a reas to ass im ila te calc ium .

(5 ) S ch u ch e rt’s 1929 c lassif ication sep a ra tes o ff th e C h o netidae as a d is tin c t fam ily f ro m th e P ro d u c tid ae . T h e d ifficu lty in tax o n o m y is th a t no sy stem atic c lassif ication fits p e r fe c tly th e com p lex v a r ia tio n s o f n a tu re itse lf. T h e sy s tem a tist ’s task is to dev ise a c lassification w h ich re p resen ts as closely as possib le th e kn o w n fac ts. T h e ea rly cho n e tids a re closely a llied to th e P lec tamb on itiin ae , be ing d is tin g u ish ed f ro m th em ch iefly by th e p resence o f ca rd in a l sp ines. S im ila rly , th e la te r ch o ne tid s a re v e ry closely a llied to th e p ro d u c tid s , w h ich a re d is tin g u ish ed by th e ir in creased sp inosity an d d en d r it ic m uscle im p ress ion s. T h e p ro d u c tid s co n stitu te a c learly -def ined g ro u p o f an in creasin g n u m b er o f g en e ra , ve ry w ide ly d is tr ib u te d , an d m o st pro lific . “ T h ey p ro d u ced th e m o st n u m ero u s, th e m o st v a r ie d , th e m ost w id esp read a n d th e la rg est b rach iopods in th e la te P alaeozo ic ” (R ay m o n d , 1939). T h e chonetids likew ise fo rm a b io log ically d is t in c t, n u m erica lly large , an d rac ia lly pro lif ic g ro u p su rv iv ing in s tre n g th th ro u g h the m a jo r p a r t o f th e P alaeozo ic ( v id e fig. 1 ), an d still m a in ta in in g its s tre n g th a f te r g iv ing r ise to the p ro d u c tid s . In m y op in ion , fu r th e rm o re , th e early chonetids a re q u ite as closely allied, to th e S tro p h o m en id ae as. the la te r chonetids a re to th e P ro d u c tid a e , a n d th e re fo re th e re a re as adequate •grounds fo r sep a ra tin g th e ch o ne tid s fro m th e p ro du c tid s as th e re a r e fo r sep a ra tin g th e cho ne tid s fro m the stro ph om en id s. I

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th e re fo re ag ree w ith S ch u ch e rt ’s su ggestion th a t they be re p re ­se n te d as tw o sep a ra te fam ilies— th e C h onetidae an d the P ro d u c tid ae .

A d a p t a t i o n s .

M o st o f th e species o f C honetes f ro m V ic to r ia a re fa ir ly th in - shelled fo rm s, an d usua lly th e re is a d irec t co rre la tio n betw een the w eight o f the shell an d th e s tren g th o f the sp ines. F o r exam ple, C. m e lb o u rn e n s is is a ligh t fo rm w ith fine sp ines, w hereas C. ro b u s ta h as h eav ie r va lves an d s tro n g e r sp ines. T h e m echanics o f these shells a re v e ry in te restin g . T h e sp ines a re ho llow , w h ich a f fo rd s s tre n g th w ith the ligh tness n eeded fo r a sem i-floating o rg a n ism ; likew ise co rru g a tio n s o f th e shell g ive stre n g th w ith l ig h tn ess. T h e shells a re usua lly f la ttish o r concave, a n d so a d ap ted to th e sem i-floa ting ( i.e ., n o t r ig id ly f ixed ) con d itio n o f a n o rgan ism a tta c h e d to a su b -s tra tu m . T h e sm all space betw een th e tw o va lves ind ica tes th a t th e an im al w as slender, an d so aga in a d a p te d by its ligh tness to th e p a r tic u la r p lace this genus h a d in th e m arin e ecology o f P alaeozo ic tim es.

So m e C h a r a c t e r i s t i c s o f t h e V i c t o r i a n F o r m s .

R efe ren c e has a lre ad y been m ade to th e se ttin g o f th e sp ines ■ on o u r fo rm s a t r ig h t ang les to the h inge-line. C h o n e tes m aor ia A llan f ro m th e R e e f to n (L o w e r D ev o n ian ) B eds o f N ew Z ea land also h as its sp ines in se rted a t r ig h t ang les as is to be seen on a spec im en in th e N a tio n a l M useum , M elbourne .

T h re e species described in th is p ap e r (C . ro b u sta , C. cressw e lli, an d C. k i l la ren s is ) h ave a w ell-defined m esia l su lcus in th e v en tra l -valve.' . T h e b io log ical ad v an tag e o f th is w ou ld be th e in creased a re a fo r m uscle a t ta c h m e n t; p 'e rhaps a lso th e su lcus w ou ld have a s im ila r ac tio n to a keel an d help to keep th e an im a l floating evenly . T h e sam e fe a tu re has been n o ted in C. va r io la ta , C. vern eu il ia n a , C. m eso loba , C. co rona ta , C. lep ida , C. a rcua ta , C. 'm a n su y i, a n d C. n ing p o en sis . R eed (1 9 2 1 ) describes th is fe a tu re in a v a r ie ty o f C. sa rc inu la ta . In th e V ic to r ia n fo rm s th e sinus is a co n stan t c h a ra c te r o f the species nam ed, w h ereas it is c laim ed to be p re sen t in C. a cu tira d ia ta on ly som etim es, an d it is no t fo u n d in a ll th e specim ens nam ed C. maoria-. A m esia l s in us is com m on in th e P ro d u c tid ae .

A n o th e r fe a tu re o f in te re s t is th e d if fe ren tia ted marg in , such as fo u n d in C. ta g g e r tyen sis , a s im ila r pheno m en on to w h ich has b een described in C. sa rc inu la ta , C. m ao r ia , C. co rona ta , an d C. sy r ta l is . T h e s tru c tu re , is in te re s tin g phy logenetica lly in v iew o f va rious m od if ications o f th e m arg in o f th e shell fou n d in o th e r S trophom enaceae, such as th e deflected m arg in in L ep ta e n a an d S tro p h o n e lla , v a r ia t io n in pap illo s ity a ro u n d th e m arg in o f the in te r io r su r fa c e in C honetes, v a r ia tio n in th e ex te rn a l o rnam en t a ro u n d th e m arg in o f som e species o f P ro d u c tu s , an d so on.

C ho n etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 131

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132 E d mu n d D . G ill:

N o t e s o n S p e o ies P r e v i o u s l y D e s cr i b e d .

C h o n e t e s ( C h o n e t e s) m e l b o u r n e n s i s C hapm an.

C h o n e te s m e lb o u r n e n s is C h a p m a n , 1903, pp . 74-76, p i. X I . , f ig s. 2 -4 .

T y p e M a t e r i a l .— T w o syn types. N a tio n a l M useum , R eg. N o. 636, is th e in te rn a l cast o f a v en tra l va lve in m icaceous, b lu ish - g rey , v e ry fin e-g ra in ed san d sto n e f ro m “ S o u th Y a r ra Im p ro v e ­m en t W o rk s .” N .M ., Reg N o. 1419, is th e in te rn a l cast o f a d o rsa l valve in h a rd , g rey ish -b row n , v e ry fin e -g ra in ed san d ston e fro m “ S ew erage tu n n e l n e a r o ld F ish m a rk e t.”

D e s c r i p t i o n o f V e n t r a l V a l v e ( N o . 6 3 6 ) .— T h is is adeco rtica ted shell, sm all, s lig h tly con vex , f lat on card in a l m arg in s, m easu r in g 5 m m . long an d 8 -5 m m . w ide. T h e p ro file rises ab o u t -75 m m . above, th e p lane jo in in g th e a n te r io r an d p o s te r io r m arg in s. S u rfa ce w ith ab o u t 80 fine, ra d ia t in g s tr iae w ith som e s ix m o re o r less even ly -spaced, s lig h tly s tro n g e r rad ii. T h e p re se rv a tio n does n o t allow o f deta iled ex am in a tio n o f th e fine s tr iae , b u t w h ere c learly d iscern ib le , increase is by b ifu rc a tio n . C ard in a l a re a n a r r o w ; ca rd in a l ang les a l i tt le m ore th a n r ig h t ang les. B eak d istinc t, b u t n o t la rge , p ro je c t in g ju s t beyond th e h inge-line . E lo n g a te pap illae p resen t, or ien ta te d to th e s tr iae . (N o t rea liz in g th a t h e w as d ea ling w ith a deco rtica ted spec im en, C hap m an described these im p ressions o f pap illae as p itt in g s in th e o u te r su r fa c e o f th e she ll.) M uscle scars in^d istingu ishab le . N o sp ines p reserved .

D e s c r i p t i o n o f D o r s a l V a l y e (N o . 1 41 9 ).— S m all shell,v e ry s ligh tly concave, m easu r in g 3 -5 m m . long , an d 6 -5 m m . w ide. S u rfa c e covered w ith n u m ero u s po o rly p reserv ed fine ra d ia t in g s tr iae , som e few being a l i tt le m o re p ro n o u n ced th an the re s t ; a c learly defined l in ea r d ep ress io n ru n s dow n th e w holp len g th o f th e ce n tre o f th e shell. F iv e long , v e ry fine sp ines p rese rv ed f ro m th e v e n tra l va lve ( tw o on one side of th e um bo an d th re e on the o th e r ) , th e longest be ing 2 -5 m m

C o m m e n t .— E x a m in a tio n o f spec im ens o th e r th a n th e syn types show s th a t C. m e lb o u rn e n s is ca rr ies ten long, p o in ted sp ines, five on each side o f th e u m b o ; th e sp ines a re set a t r igh t ang les to the h inge-line o r cu rv ed o u tw ard s sligh tly . E x a rh in a tion o f a n u m b er o f spec im ens a lso show s th a t th e in te r io rs o f b o th , va lves a re covered w ith fine pap illae, w h ich a re e longate , se t in th e in te r- s tr ia te spaces, an d o rien ta te d to th e d irec tio n o f th e str iae . T h e ex te rn a l o rn a m e n t ap p e a rs a lso on th e in te r io rs o f th e valves, b u t

, less d is tin c tly , an d is absen t w here th e m uscle sca rs a re w ell developed.

I n C . .m e lb o u rn en s is th e re is a s tro n g e r rib do w n th e m id d le o f th e v en tra l va lve an d a co rresp o n d in g l in ea r dep ress io n on the do rsa l valve. T h is b ip a r t i t io n m ay be co m p ared w ith th e m esial

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s in u s fo u n d in a n u m b er o f species o f C h on etes ( v id e p. 131 ). S im ila r b ip a rt i t io n has been described in C. novasco tica (M c L e a rn . 1924) and C. a ro o sto o ken s is (C la rk e , 1907).

C. m e lb o u rn en s is is a va luab le in d ex fossil, b u t som e' ca re is necessary to e n su re th a t specim ens rea lly do belong to th is species. T h e a u th o r has n o ted a v a r ie ty o f fo rm s w h ich have been re fe r re d in co llections to th is species, b u t w h ich do no t con fo rm to the type. E x ten s iv e co llecting an d in tens ive s tu d y w ill have to l>e u n d e rta k en to sep ara te o u t these v a r io u s fo rm s an d acco rd th em th e ir p ro p e r s ta tus. S h e r ra rd and K eb le (1 9 3 7 ) record ed C. m elb o u rn e n s is f ro m N ew S o u th W ales. M rs S h e r ra rd k ind ly a llow ed m e to ex am ine these specim ens. H o w ev er, th ey are possib ly sm all s tro p h eo d o n tid s a n d certa in ly n o t C honetes. M any s tro p h eo d o n tid s sim u la te C honetes, e.g., S tro p h e o d o n ta b ipa rtita (C h a p m a n ) f ro m th e Y e r in g ia n rocks o f V ic to r ia . T h om as (1 9 3 7 ) has used C. m e lb o u rn e n s is as a zone fossil in the series o f sed im en ts a t H e a th co te , b u t th is fo rm is n o t C h o n e tes e ither, if th e specim ens co llected by P ro fe sso r H il ls f ro m th is ho rizon a re th e fo rm to w h ich T h o m as re fe rs . L ik e th e N ew S ou th W ales fossil, i t is devo id o f sp ines an d on ly s im u la tes C ho n etes in its g enera l fo rm an d o rn am en t. T h e reco rd o f C. m e lb o u rn en s is f ro m “ A u b u rn ” an d “ B alw yn, n ea r T e m p le s to w e ” (C hap m an ,1914, p. 2 1 5 ) is a lso in co rrec t.

A ff in it ies .— C. m e lb o u rn e n s is is. com parab le w ith C. n ovasco tica o f th e N o rth A m erican succession an d C. s tr ia te lla o f the E u ro p e an succession. C. novasco tica occurs in th e M o y d a rt (L o w e r L u d lo w ag e) a n d th e S toneh ou se (U p p e r L ud low ag e ) o f A risa ig , N ova S co tia (M c L e a rn , 1 9 24 ), an d has also been re co rd ed f ro m the M issen den B o re in E n g lan d (S tra w , 1932). M cL earn says (p . 6 5 ) th a t C. n ovasco tica d if fe rs f ro m C. str ia te lla in th e deve lopm en t o f a - s tro n g e r m ed ian s tr ia on th e v en tra l va lve, w h ich fe a tu re is a lso fo u n d in C. m e lb o u rn en s is . C. nova sco tica has th e sam e n um b er o f sp ines as C. m e lb o u rn en s is , bu t th ey a re m inu te , w h e reas those o f th e la tte r species a re as lo ng as th re e -q u a r te rs o f th e len g th o f th e shell. T h e su rfa ce o f C. novasco tica has m o re n u m ero u s s tr iae , b u t fo rm s w ith co a rser o rn am en t a re k now n (M c L ea rn , 1924, p. 6 6 ) . T h e s tr iae a re flex u ou s in C. n ovasco tica b u t s tra ig h t in C. m elb o u rn en s is . T h ese tw o species a re d is tin c t, b u t c losely ap p ro x im a te one an o th e r , an d p ro v id e a n o th e r in te re s tin g con n ec ting lin k betw een th e fau n as o f th is age in N o r th A m erica an d A u stra lia . T h e sp ines o f C. s tr ia te lla a re heavy a n d sh o rt and set a t an ang le o f ab o u t 45 ° to th e h inge-line, w h ereas th o se o f C. m e lb o u rn e n s is a re long an d s len d er an d set a t r ig h t ang les to the h inge-line. _ T h e do rsa l valve is defin ite ly concave in C. s tr ia te lla , w h ereas it is f la t o r a lm ost so in C. m e lb o u rn en sis . C. s tr ia te lla is ch arac te ris tica lly la rg e r an d m ore tran sv e rse th an th e V ic to r ia n species. H o w ev er, th e obv ious s im ila r ity is str ik in g .

C ho n etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 133

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134 E dmu n d , D . G ill:

C h o n e t e s (C h o n e t e s) r o b u s t a C hapm an.

( P I . V I I I . , f ig . 5 .)

C h o n e te s r o b u s ta C h a p m a n , 1903, pp . 76-77 , p i. X I I . , f ig . 8.

T y p e M a t e r i a l .— T w o valves in s i tu (h o lo ty p e ) , N a tio n a l M useum , R eg. N o. 1417; ab o u t ha lf o f v e n tra l valve, an d m ost of d o rsa l valve, in in d u ra te d f ine-g ra ined san d sto n e fro m “ N o rth o f L i ly d a le ” (loc. 3, v id e G ill, 1940, p. 2 5 8 ).

D e s c r ip t io n .— C oncave-convex do rso -v en tra lly , 19 m m . wide: (b u t th is n o t fu ll w id th as one ca rd in a l ang le b ro ke n ) , an d 1 2 mm., long. O u tl in e sub -sem ic ircu lar. Shell tu m id w ith m esial s inus and a s lig h t f la tten in g on th e ca rd ina l ang les ; lon g itu d in a l p ro f ile rises, ab o u t 6 m m . above th e p lane jo in in g th e a n te r io r a n d p o ster io r m arg in s o f th e shell.. H in g e- lin e m ostly absen t, b ut l i tt le less, th an g re a te s t w id th o f shell ow ing to s ligh tly ob tuse ca rd in a l angles. A b o u t th ir ty -s ix fa ir ly sh a rp , h igh ribs (co u n te d in m idd le o f she ll) som e b ifu rc a t in g an te r io r ly . O th e r specim ens suggest th a t fo u r s tro p g sp ines on each side o f the um bo (e ig h t in a ll) is th e n o rm a l n u m ber. T h e o u te r sp ine in the type spec im en has a s lig h t in c lina tion ou tw ard s . T h e do rsa l va lve of th e type spec im en fo llow s fa ir ly c losely th e co n to urs o f th e v en tra l valve, th e g re a tes t d is tance , o f sep a ra tio n be ing 1 -5 m m . S im ila r o rn a m e n ta tio n to th a t on th e v e n tra l va lve is p reserved . T h e o rn am en ta tio n con tinues th ro u g h to th e in te r io r o f bo th valves. A s' is th e case w ith p rac tica lly all fossils f ro m th e L i ly ­da le d is tr ic t, on ly casts an d m ou lds a re p reserv ed , the o rig ina l shell m ater ia l hav in g been leached aw ay.

Co m m e n t .— T h e s tu d y o f spec im ens o th e r th a n th e type shows, th a t th e beak is inconsp icuous, scarce ly p ro je c tin g beyond the- h in g e - l in e ; the ca rd in a l a rea is f lat an d w e ll-d ev elo p ed ; m ed ian sep tu m sh o rt an d n a r ro w ; tee th an d m uscle sca rs n o t observed . T h e n u m b er Of r ibs has been no ted to v a ry f ro m 24 to 36. C. ro b u sta is closely a llied to C. k il la ren s is sp. nov., an d C. c re ssw e ll i C hapm an.

O ccu rren ce.— B esides th e localities m en tio n ed above, C. ro b u s ta is know n f ro m “W ilso n ’s ” (loc. 2 ) , H u l l- ro ad , M oo roo lba rk (loc. 13 ), and Sy m e’s T u n n e l, K i l la ra (loc. 3 4 ).

C h o n e t e s (C h o n e t e s) c r e s s w e l l i C hapm an.

C h o n e te s c r e s s w e l l i C h a p m a n , 1903, pp . 77-78, p i. X I I . , ' f ig . 7.

T y p e M a t e r i a l .— In te rn a l cast o f v en tra l valve (h o lo ty p e ) in in d u ra te d m u d sto n e f ro m “ N o r th o f L i ly d a le ” (N a tio na l M useum , R eg . N o. 6 5 2 ).

D e s c r i p t i o n .— Shell ap p ro x im a te ly sem i-c ircu la r in ou tline, be ing 7 -5 m m . long an d 13 m m . w ide. V e n tra l valve convex r is in g ab o u t 3 m m . above the p lane jo in in g th e a n ter io r a n d

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p o s te r io r m arg in s. B eak inconsp icuous, scarce ly p roje c tin g beyond h inge-line. H in g e- lin e s tra ig h t an d n early equa l to g re a tes t w id th o f shell. C ard ina l ang les a p p ro x im a te ly r ig h t ang les. T e e th fine. S h o rt, fine m ed ian sep tu m 1 -5 mm . long. V e ry n a r ro w ca rd in a l a rea. S om e 40 fine, ro u n d e d ribs ra d ia te f ro m um bo, b ifu rc a tio n s in c reas in g n u m b er o f r ibs at m arg in to- • ab o u t 54. O th e r spec im ens show sp ines a t r ig h t ang les to the h in g e - l in e ; th ey a re f in er th a n tho se on C. robusta . Conspicuous- m esia l s inus p resen t. F a in t traces o f co n cen tr ic lines o f g ro w th • observed . S p ines on a spec im en f ro m H u ll- ro a d , L ilyda le (loc. 1) a re f igu red (P I. V I I I . , fig. 5 ) .

H o r i z o n .— -Y ering ian (L o w e r D e v o n ia n ).

C o m m e n t .— T h is spec ies is v e ry c losely re la ted to C. ro b u sta ,: th e ch ie f d ifferences being (as C hapm an re m a rk e d ) in th e a lto ­g e th e r s to u te r bu ild an d fe w er rad ii in C. ro b u sta . T h e ribs are- fine an d ro u n d e d in C. cressvaelli b u t h igh a n d sh a rp in C. robusta . C hapm an also d rew a tte n tio n to th e s im ila r ity betw een C. c ressw e ll i an d C. austra lis M cC oy f ro m th e M id d le D evon ian rocks o f V ic to r ia . ’ T h is is th e m o re s ign if ican t now in v iew o f th e m uch m o re closely a p p ro x im a te d ages a ttr ib u te d to th e L i ly ­da le an d B u ch an B eds. C. au stra lis occurs in g re a t n u m b ers in th e B u ch an an d s im ila r lim estones, b u t no C h o n etes has been fo u n d in th e C ave H il l lim estone beds a t L ilydale. B rach io p od s, ex cep t fo r A tr y p a re ticu la r is , a re v e ry ra re a t Cave H ill.

T h e re is a close s im ila r ity betw een the chonetids of- V ic to r ia a n d those o f th e D evo n ian rocks o f F re n c h In d o ch ina. T h e D ev o n ian o f N ew Z ea land , E a s te rn A u s tra lia , an d In d o ch in a ap p e a r to c o n s titu te a w ell-defined zone. A tte n t io n has a lre ad y been d irec ted to th e s im ila r ity betw een c e rta in tr ilo b ites in th is zone (G ill, 1944). C h o n etes n o n g p o en s is (M an su y , 1919, pp. 26 - 27, P la te V ., fig. 4a, b ) is v e ry m uch like C. c ressw e lli C hapm an. T h e g en era l p ro p o rtio n s o f th e shell a re th e sam e, th e n u m b e r o f o rn a m e n tin g ribs is abo u t th e sam e, a n d bo th have a w ell- m ark ed m esial s inus, and sh o rt fine m ed ian sep tum . H o w ev er, the r ib s a re ro u n d e d in C. c ressw e ll i a n d ra ised an d . sh a rp in C. n o n g p o en sis , as th ey a re also in C. ro b u s ta w h ich is a c lose v a r ia n t o f C. cressw e lli. U n fo r tu n a te ly , th e sp ines o f C. n o n g p o en sis . a re no t know n. A s o u r know ledge s tan d s a t p resen t, th e re is v e ry litt le to sep a ra te C. c ressw e ll i an d C. n o ngpoensis . T h e spec im ens f ig u red as C. h a rd ren s is (M a n su y , 1921, P la te I I . , figs. 5a-c"), C. c f. m arga r itacea (M a n su y , 1916a, P la te I ., fig. 1 1 ), C. in d o s in en s is , C. la c ro ix i, C. lan teno is i, a n d C. cf. str ia te lla (M a n su y , 1916b, P la te V I I . , figs. 5 -8 ) , C. ze il i, an d C. m a n su y i (P a tte , 1926) a re co m parab le w ith o u r V ic to r ia n types. I t is in te re s tin g to no te th e p resence o f a m esial s inus on som e o f these fo rm s, an d th e o rien ta tio n o f the sp ines a t r ig h t ang les to the h inge-line, as in o u r species. C. la n ten o is i an d C. la c ro ix i have th e long m ed ian sep tu m no ted in C. ta g g er tyen sis .

C ho n etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia ,. 135'.

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136 E d mu n d D . G ill:

C h o n e t e s (C h o n e t e s) a u s t r a l i s M cC oy.

C h o n e te s a u s t r a l i s M c C o y , 1876, p . 17, p i. X X X V . , f ig s . 3 -5 .

U n fo r tu n a te ly , the N a tio n a l M u seu m is un ab le a t p resen t to locate th e type specim en o f C. austra lis . F u r th e r desc rip tio n o f th is fo rm , an d com m ent, a re th e re fo re w ith h e ld in th e hope th a t th e type m ay be fou n d . A s th e specim en con cerned is p robab ly on ly m isp laced an d no t rea lly lost, i t is n o t p ro posed to choose a lecto type.

D e s cr i p t i o n s o f N e w S p e c i es .

C h o n e t e s .(C h o n e t e s) b o w i e a e , sp. n o v .

(P I . V I I I . , f ig s. 1 a n d 2 .)

T y p e M a t e r i a l .— E x te rn a l cast an d in te rn a l m ou ld (sy n ty p es) o f a v en tra l valve in in d u ra te d fa w n shale f ro m S yme’s Q u a rry , K i l la ra , p re sen ted to the U n iv e rs ity o f M elb o u rne , G eology D e ­p a r tm e n t M u seu m (c o u n te rp a r ts , R eg. N os. 1908-9 ). Co llected by M rs. R . B ow ie, a f te r w hom th e species is nam ed.

D e s c r i p t i o n .— Shell 17 m m . long (m ea su red in one p lan e ) and 19 m m . w ide a t th e w id est p a r t ; m idd le o f th e shell v e ry tu m id , b u t p rac tica lly flat on th e c a rd in a l ex trem ities . Card in a l ang les ob tuse. H in g e- lin e s tra ig h t an d less th a n g re a te s t w id th o f she ll.' C ard in a l a re a fla t, fu ll w id th o f h inge-line , para lle l to p lane o f shell, an d ab o u t 1 m m . w ide. E ig h t long, even ly -spaced spines, fa ir ly s lend er, p ro je c t f ro m th e ca rd in a l m arg in a t r ig h t ang les to the h in g e-lin e ; longest sp ine p rese rv ed is 7 m m . B eak p ro jec ts a l i tt le beyond th e h inge-line. T h in m ed ian sep tu m a b o u t 4 m m . long, w h ich is low a t its a n te r io r end w h e re it r ises f ro m the floor o f the shell, and becom es h ig h er to w a rd s its p o s te rio r end. In te r io r o f valve finely pap illose a ro u n d ca rd in a l e x tre m it ie s ; th e re a re traces o f p ap illo s ity e lsew here on th e inte rn a l cast, w h ich suggests th a t th e w ho le in te r io r o f th e valve w as pap illose. T h e type specim en is c ru sh ed s ligh tly by la te ra l p ressure . T e e th sm all an d su p p o rted by den ta l lam ellae a lm o st p a ra lle l w ith th e h inge- line. B etw een 50 an d 60 fine ro u n d e d ribs (c o u n te d a t the a n te r io r m a rg in ) ra d ia te f ro m th e u m b o ; increases by b ifu rc a tio n .

H o r i z o n .— Y erin g ian (L o w e r D e v o n ia n ) .

C o m m e n t .— T h is species sh ares w ith C. p ro d u c to id a an d C. ta g g e r tyen sis g en era l p ro d u c tid p ro p o r tio n s . I t p ro v id es a f u r ­th e r link betw een th e fau n u les o f L ilyda le a n d K il la ra . O n th e p iece o f rock co n ta in in g th e in te rn a l cas t th e re is a lso a spec im en o f P le u r o d ic ty u m m e g a s to m u m D u n , an d on th e p iece co n ta in in g th e ex te rn a l m ou ld a pyg id iu m o f L ic h a s ( E uarg .es) a u stra lis M cC oy, and B ey r ic h ia sp. can be seen.

O c c u r r e n c e .— S y m e’s Q u a r ry (loc. 3 5 ) , Sev ille Q u a r ry (loc. 3 7 ) , M e lb o u rn e H il l , L i ly d a le (loc. 7 ) , a n d d o u b tful ly a t H u l l- ro ad , L ilyda le (loc. 1 ). , .

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C hon etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 137

C h o n e t e s (C h o n e t e s) t a g g e r t y e n s i s, s p . n o v .

( P I . V I I I . , f ig s . 6 a n d 8 .)

jT y p e M a t e r i a l .— E x te rn a l cast an d in te rn a l m ou ld (sy n ty p es)

o f a v en tra l va lve in h igh ly in d u ra te d f ine-g ra ined g rey san d sto n e fro m B lue H il ls , T a g g e rty , co llected by P ro fe sso r E. S. H il ls and p re se rv ed in th e U n iv e rs ity o f M e lb o u rne G eology D e p artm en t M u seu m (c o u n te rp a r ts , R eg. N os. 1910, 1911 ).

D e s c r i p t i o n .— Shell 22 to 24 nim . w ide (o n e ca rd ina l ex tre m ity is dam aged an d so an ac cu ra te m easu rem en t is n o t p o ss ib le ), 16 m m . lo n g ; pro file rises 6 m m . above th e p lan e jo in in g th e a n te r io r an d p o s te r io r m arg ins. V a lve v e ry convex a n d f la ttened on th e ca rd in a l ex trem ities ( “ o re ille ttes ” o f de K o n in c k ) . E x te rn a l m ou ld show s 70 to 80 fine r ibs a t th e a n te r io r m a rg in ; increases by b i fu rc a ­tion . T h e ribs scarce ly show on th e in te rn a l cast excep t fo r a s tr ip 3 to 4 m m . w ide ro u n d th e a n te r io r p e r im e te r o f the shell. T h is is an a rea ou ts id e th e p henom ena lly la rg e m uscle scars, a n d is finely p a p i l la te ; s ligh tly h eav ie r pap illae occu r on the o re ille ttes. L a rg e , flabellate, inc ised ( i.e ., ra ised in the m o u ld ) d id u c to rs ex ten d th re e -q u a r te rs leng th o f shell, enc losing inc ised ad d u c to rs 4 -5 m m . long. B eak inconsp icuous, p ro je c tin g ju s t beyond th e ca rd ina l line. C ard in a l a rea low a t th e ex trem ities b u t r is ing to ab o u t 2 m m . in th e c e n tre —v ery h igh fo r C honetes. T e e th v e ry s tro n g . Shell th ick . M ed ian sep tu m s tro ng an d h igh a t th e ca rd in a l e n d ; a t least 6 -5 m m . long (b e tw een th e cas t and m ou ld a l i tt le m ater ia l h as in f i l tra ted an d th e septu m m ay be lon ger th a n s ta te d ) . T h e re is th e su ggestion o f a sep tu m dow n a lm ost th e e n tire leng th o f th e shell. In th e o th e r specim en figu red (R eg . N o. 1 9 1 2 ,'p a ra ty p e , P la te V I I I . , fig. 6 ) , th e sep tum is seen to ru n p rac tica lly th e w ho le leng th o f th e b ig ad d u c to r scars. N o sp ines o r sp ine bases can be d is tin g u ish ed on the type specim en, b u t in th e assoc ia ted spec im en sp in e bases a re p resen t. T h e on ly d iffe rence b e tw een th e ty p e spec im en an d th e o th e r is th a t th e la tte r is a l i t t le m o re tra n sv e rse in p ro po rtio n s , an d the m uscle sca rs a re a litt le m o re deep ly incised. B o th these v a r ia ­tions a re k n o w n to occu r w ith in c reas in g age in C honetes.

H o r i z o n .— P ro b ab ly Y e r in g ia n (L o w e r D e v o n ia n ).

O c c u r r e n c e .— B lue H il ls , T a g g e rty , V ic to r ia . P ro fe sso r H il ls (1 9 2 9 ) m en tions th e co llec tion o f C h o n etes sp. f ro m T ag g e rty , b u t th e specim ens figu red h e re in w e re co llected subsequen tly by h im .

C o m m e n t . — C ho n etes ta g g e r tye n s is h as a n u m b er o f affin ities w ith C. sa rc in u la ta (S c h lo th e im ) as figu red by de K o n in ck ( 1 8 4 7 )

in PI. X X ., fig. 1 5 e . T h e re th e sam e flabellate, inc ised m uscle

1 5 5 1 / 4 5 . - 9

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138 E d mu n d D . G tll:

scars a re seen w ith bu t fa in t trace o f th e ribs o f th e ex te rn a l o rn am en t, a p u n c ta te m arg in is p re sen t sho w in g m o re c lea rly the: ex te rn a l o rnam en t, a n d a v ery long m ed ian sep tum . Th e size o f th e m uscles, th e len g th o f th e sep tum , an d th e h e igh t o f th e v en tra l ca rd in a l a rea a re all phenom ena l, an d th u s g ive m o re p o in t to th e com parison . H o w ev er, th e ex te rn a l o rn am e n t as described by de K o n in ck is qu ite d if fe ren t f ro m th at o f o u r species, th e ribs being m an y fe w er in C. sa rc inu la ta , p ra c tica l ly all b ifu rc a tin g , a n d d o ing so a t ab o u t th e sam e d istance f ro m th e um bo. C. sa rc in u la ta is one o f the m ost ch a rac te r is t ic fossils o f th e E u ro p e an L o w er D evon ian assem blage. C. m aor ia a n d C. n ig r icans (A l lan , 1935; S h ir ley , 19 3 8 ), f ro m th e N ew Z ea lan d L o w er D evon ian , a re o f th is sam e type, bu t the m uscle a re a is sm a lle r an d th e m ed ian sep tum sh o rte r . H o w ev er, a spec im en o f C. m aor ia in th e N a tio na l M u seum , M e lbou rne , has a lo n g e r sep tu m th an th a t f igu red fo r th e ho lo type. A llan says, “ T h e g en era l app earan ce o f th is species suggests such g en e ra as P lec ta m b o n ites P a n d e r , b u t it p ro b ab ly belongs to C h o n etes.”' T h e g en e r ic .p o s itio n o f C. m a o r ia is con firm ed b y th e p resence o f one sp ine base a n d p robab ly a second on th e spec im en in th e N atio n a l M useum , M elbourne . L ike C. sa rc inu la ta , th e N ew Z ea land species is h igh ly pap illose on th e in te r io r su r fa c e excep t on th e m uscle scars. F ro m A l la n ’s f igu re , i t ap p ears th a t C. m a o r ia has a m esial s inus like C. c ressw e lli and C. robusta,. H o w ­ev er, th is is no t p re sen t in th e M e lb o u rn e specim en, n o r is th e “ a n te r io r m arg in som ew h at sh a rp ly b en t to p ro d u ce a L ep taen id - like ap p earan ce .” T h e la t te r m ay be due to p re ssu re in th e rock m a tr ix .

C. ta g g e r tyen sis is also like C. u n ke le n s is (D a h m e r, 1936, 1937 ), w h ich is f ro m th e S iegen ian o f U nk e l, and belongs to th eC. sa rc inu la ta gens.

C h o n e t e s, ( C h o n e t e s) p s i l o p l i a , sp. n o v .

(P I . V I I I . , f ig . IS . )

T y p e M a t e r i a l .— H o lo ty p e co nsisting o f a v en tra l valve in- b lu ish -g rey m u d sto n e fro m K il la ra co llec ted by M r. F . C hapm an,, an d lodged in th e N a tio n a l M useum , M e lb o u rn e (R eg . N o. 14519). T h e fossil is p robab ly f ro m loc. 34 (G ill, 1944).

D e s c r i p t i o n .— V a lv e 13 m m . w ide, 6 -5 m m . long, an d heigh t (d is tan ce pro file rises above p lane jo in in g an te r ior an d p o s te r io r m arg in s ) ab o u t 1 -5 m m . T h e card ina l ang les a re ap p ro x im a te ly r ig h t ang les so th a t the o u tlin e o f th e valve is not exactly sem i­c ircu la r, b u t ten d s to w ard s th e su b -re c tan g u la r ; the rad iu s o f the valve is 7 - 5 m m . h a lf w ay betw een the ca rd in a l ang le an d the cen tre o f the p o s te r io r edge o f the shell. V alve som ew hat f la ttened on th e card in a l ex tre m it ies an d ro u n d th e pe r im e te r, fo rm in g a m arg in a l

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f lange com parab le w ith th a t in C. ta g g er tyen sis . T h e m uscle scars a re n o t d is tinc t, bu t ins ide th e flange re fe r re d to th e re is a ra ised a re a on th e cast w here th e o rn am en t is less d is tin ct an d th is m ay w ell be in te rp re te d as inc ised m uscle scars on th e o rig ina l shell. T h e ex te rn a l o rn a m e n t consists o f b e tw een 70 an d 80 fine, som e­w ha t s inuous, ro u n d e d ribs, in c reas in g in n u m b er by b ifu rc a tio n . In te r io r o f va lve finely pap illa te . B eak insign if ican t, n o t p ro ­jec tin g beyond th e h inge-line. C ard in a l a re a ab o u t -5 m m . w ide, sm oo th , an d fa ir ly re g u la r in w id th . T w o sp ines set a t r ig h t ang les to th e h inge-line a re p reserv ed , bu t n e ith e r is co mp le te ; one f ra g m e n t is -75 m m . long an d the o th e r 4 m m . T h ese sp ines are v e ry s len der fo r a shell o f th is size— hence th e tr iv ia l nam e. Im p ress io n o f one to o th on ly ( th e o th e r s ide is s ligh tly b roken a w a y ) , and th a t is m inu te . F in e m ed ian sep tu m 1 -75 m m . long.

H o r i z o n .— Y e rin g ian (L o w e r D ev o n ia n ).

C o m m e n t .— T h is species is o f the C. sa rc inu la ta ty pe w ith large incised m uscle sears g iv ing a d if fe ren tia ted m arg in to the in te r io r o f th e v en tra l valve. T h e shell is o f a lto g e th e r l ig h te r co n stru c tio n th a n C. ta g g e r tye n s is (w ith w h ich it m ay be c o m p a re d ), an d the m ed ian sep tum is p ro p o rtio n a te ly very m uch sh o rte r . T h e sp ines a re notab le.

C h o n e t e s ( C h o n e t e s) r u d d o c k e n s i s, s p . n o v .

( P I . V I I I . , f ig . 10 .)

T y p e M a t e r i a l .— H olo typ e , consisting o f an in te rn a l cast o f a

v en tra l valve in in d u ra te d o live-g rey m u d sto ne f ro m R u d d o ck ’s Q u a r ry (loc. 2 0 ) , p re sen ted to the U n iv e rs ity o f M elbou rne G eology D e p a rtm en t M u seu m (R eg . N o. 1914).

D e s c r i p t i o n .— Shell 7 m m . w ide an d 5 - 5 m m . lo n g ; lo n g itud ina l pro file rises ab o u t 2 m m . above a line jo in in g th e a n te r io r an d p o s te r io r m arg in s o f th e valve. C ard ina l ang les ap pro x im a te ly r ig h t ang les. V a lve less convex on ca rd in a l ex trem ities. B eak insign if ican t. T h e tw o halves o f the card in a l a rea fo rm an ang le o f abo u t 1 7 0 ° .

R ibs as seen in in te rn a l cast l in ear an d o f ro u n d ed c ro ss-se c t io n ; fine p i t t in g betw een ribs, i.e., in te r io r o f va lve finely pap il lo se ; ab o u t 40 r ibs h a lf w ay betw een a n te r io r an d p o s te r io r m arg in s, a n d ab o u t 50 at th e a n te r io r m a rg in ; increase by b ifu rc a tio n . W ha t appears to be a l in ea r m ed ian sep tum s tre tch es n early h a lf w ay do w n the m idd le o f th e va lve f ro m th e um bo. C ard in a l a re a v ery n a rro w , an d tee th n o t seen. P a r ts o f tw o sp ines p re se rv ed on each side o f th e u m b o ; sp ines long an d th in , set m ore o r less a t r ig h t ang les to th e h in g e - l in e ; longest sp ine p re sen t 3 -5 m m .

H o r i z o n .— Y e rin g ian (L o w e r D e v o n ia n ).

C h onetidae f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 139

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140 E d mu n d D . G ill:

O c c u r r e n c e .— In th e L ily da le D is tr ic t th e new species is k n o w n fro m R u d d o c k ’s Q u a r ry (loc. 29, an d f ro m h e re th e tr iv ia l n a m e ) , R u d d o ck ’s C o rn e r (loc. 2 1 ) , E d w a rd -ro a d H il l ( loc. 2 2 ) , W est o f L ilyda le C em etery (loc.. 2 3 ) , V ic to r ia -ro a d cu tt in g (loc. 2 4 ) , “ D evon P a rk ” W e st (loc. 2 5 ) , “ D evon P a rk ” N o rth (loc. 2 6 ) , N o r th o f R u d d o c k ’s (loc. 3 9 ) . M an ch este r-ro ad , M ooroo l- b a rk ( la rg e c u tt in g n o r th o f s ta tio n — a new lo ca li ty) , S m a le ’s F a rm (o n th e w est s ide o f E d w a rd -ro a d , n o r th o f R u dd o ck ’s— a new lo ca li ty ) . I t has a lso been co llected f ro m the K in g lak e D is tr ic t f ro m “ n ea r S tra th C reek ” by P ro fe sso r E . S. H il ls (U n iv . Geol. D ep t., M us., R eg. N o. 1916) ; a sm all P le u ro d ic ty u m m e g a s to m u m is p re sen t on th e sam e p iece o f rock.

C o m m e n t .— T h e re is a good deal o f v a r ia t io n in th e g ro u p o f shells a t p re sen t inc luded u n d e r C. ru d d o ck en s is . T h e type spec im en is su b -q u a d ra te in o u tlin e w ith 40 to 50 stra ig h t l in ear ribs. A n o th e r spec im en no ted is t ra n sv e rse in ou tline , w ith 30 to 40 s tro n g e r r ibs w h ich a re som ew hat s in u o u s .. In te rm e d ia te stages betw een th e ty p e an d th is la tte r spec im en h av e been observed . I t is no t c lea r y e t how ( i f a t a ll) th is com pact g ro u p sh ou ld be sub ­d iv ided , b u t a deta iled s tu d y o f a la rg e co llection w ill no doub t so lve the p rob lem . C h o n etes ru d d o c k e n s is has affin ities w ithC. se tig e ra H a ll , w h ich has s im ila r p ro p o rtio n s , o rn am en t, and o r ie n ta tio n o f sp ines (a t r ig h t ang les to th e h in g e- l in e ) ._ O u r spec ies has fe w er a n d d if fe ren t sp ines. T h o se o f o ur species a re re m a rk ab ly long an d s lend er, so m uch so th a t it is su rp r is in g th a t so m any have been p reserv ed . T h e w a te rs in w h ich the enc losing sed im en ts w ere la id dow n m u st h av e been fa ir ly qu iet, a n in fe ren ce w h ich m ay also be m ade f ro m th e fineness o f tho se sed im en ts. O ne shell f ro m R u d d o c k ’s Q u a rry , 4 -5 m m . long, h as p re se rv ed a sp ine 8 m m . long, an d it ends a b ru p tly suggesting th a t i t w as even lo n g er o rig ina lly . In th e E u ro p e a n fac ies, C. ru d d o c k e n s is seem s to find its affin ities w ith C. so ro r B a rran d e .

C h o n e t e s (C h o n e t e s) k i l l a r e n s i s , sp. n o v .

(P I . V I I I . , f ig .1 4 . )

T y p e M a t e r i a l .— In te rn a l cast o f a v en tra l va lve (h o lo ty p e ) in b lu ish -g rey in d u ra te d m u d sto n e f ro m S y m e ’s T u n n el, K i l la ra ( loc. 3 4 ) , p resen ted to th e U n iv e rs ity o f M e lb o u rn e G eology D e p a rtm e n t M u seu m (R eg . N o. 1915).

D e s c r i p t i o n .— Shell 20 m m . w ide an d 17 m m . lo n g ; evenly tu m id ex cep t fo r m esia l s inus and a s ligh t f la tten ing on the ca rd in a l a n g le s ; lo n g itu d in a l p ro file r ises 5 m m . above th e line jo in in g th e a n te r io r an d p o s te r io r m arg ins o f th e shell. M esia l su lcus ab ou t 1 m m . deep, and ab o u t th e w id th o f five ribs. C ard in a l ang les ap p ro x im a te ly 115°. C ard ina l a rea nea r ly s t ra ig h t , b u t th e tw o halves' o f th e line fo rm a v e r te x a t the um bo. R ibs

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(o n th e in te rn a l c a s t) sh a rp an d h igh , w ith b i fu rc atio n s b u t no in te rc a la t io n s; n u m b er 34 h a lf w ay betw een th e an ter io r an d the p o ste r io r m arg in s, an d 3 7 a t th e an te r io r m a rg in ; s ligh t p u n c ta tio n b etw een th e ribs r ig h t in th e ca rd in a l ang les. P ro b ab ly ten v e ry sh o rt, fine, som ew hat s inuous sp ines ran g ed along th e ca rd in a l m arg in p e rp en d icu la r to th e h in g e - l in e ; m ost com p lete sp ine p re sen t 1 • 5 m m . long. C ard in a l a rea v ery n arro w . B eak sm all, d is tin c t, p ro jec tin g s ligh tly beyond th e h inge-line. M ed ian sep tum ab o u t 3 m m . long, n o t end ing a b ru p tly b u t tap er in g aw ay on to th e floor o f the she ll; sep tum ab o u t l /6 th m m . w ide, le e th

strong .

H o r i z o n .— Y erin g ia n (L o w e r D e v o n ia n ).

. C o m m e n t .— T h is new species is com parab le w ith C. ro bu sta w h ich occurs in th e sam e beds. T h e sp ines a re long , s tra ig h t, an d s tro n g in C. ro b u sta , b u t sh o rt, fine, an d s in u ou s in C .

k illa rensis.

O c c u r r e n c e .— A fo rm v ery s im ila r to C. k il la ren s is o ccu is in th e so f t fa w n m u dstones o f M e lb o u rn e H il l, L ilyda le (loc. 7 ) . T h e sp ines a re o f th e sam e k ind , b u t th e ribs a re mo re n u m ero u s, an d th e m esia l s inus v e ry shallow . H o w ev er, fo r th e tim e be ing it is inc luded in th is species. I n an y case, th e fossil co n stitu tes an o th e r in te re stin g link betw een th e beds a t K i l la ra an d those a t

L ilydale.

C h o n e t e s (C h o n e t e s) p r o d u c t o i d a , sp. n o v .

( P I . V I I I , f igs.. 7 a n d 12.)

T y p e M a t e r i a l .— In te rn a l cast o f a v en tra l v a l v e (h o lo ty p e ) in in d u ra te d , f ine-g ra ined , faw n san d sto n e f ro m L ilyda le , V ic ­to r ia . C o llected by R ev e ren d A . W . C ressw ell, M . A . , f ro m “ N o rth o f L i ly d a le ” (loc. 3 ) , a n d p resen ted to th e Na tio n a l M useum , M elb ou rn e (R eg . N o. 14520).

D e s c r i p t i o n .— L en g th o f shell (m ea su red in one p lane a n d n o t fo llow ing obesity o f she ll) 17 m m ., an d w id th 21 m m., lo n g i­tud in a l pro file rises ab o u t 7 m m . above a line jo in in g the a n te r io r an d p o s te r io r m arg in s o f th e 'sh e ll . Shell v e ry tu m id , b u t fa ir ly flat on th e ca rd in a l m arg in s, s im u la tin g p ro d u c to id p ro p o r tio n s— hence the tr iv ia l nam e. C ard in a l ang les dam aged , b ut p ro b ab ly s ligh tly obtuse. H in g e- lin e s tra ig h t. R ibs (o n in tern a l c a s t) sh a rp an d h igh , b u t have the ap p earan ce o f be ing w orn o ff on th e a n te r io r p a r t o f th e ty p e spec im en (c o m p are o th e r figu red specim en, N a tio n a l M u seum , R eg. N o . 14521— h y p o ty p e ), n u m b er 31 h a lf w ay betw een th e a n te r io r an d p o ste r io r m a rg in s ; increases by b ifu rca tio n . U m b o n a l a re a h igh ly a rch ed a n d o v e r­hangs h inge-line p ro d u c tid - fash io n . T h e sp ine bases p re sen t ind ica te e igh t s tro n g sp ines a lon g th e ca rd in a l m arg in , probably

C honetidae f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 141

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142 E d mu n d D . G ill:

a t r ig h t ang les to the h inge-line. C ard in a l a re a n arro w . M ed ian sep tum 3 m m . long, en d ing fa ir ly a b ru p tly ; h igh , and ab o u t ■ J m m . w ide. T ee th stro n g .

H o r i z o n .— Y erin g ian (L o w e r D e v o n ia n ).

Co m m e n t .— T h is new species is v e ry s im ila r in ex te rn a l ap p earan ce to C. h em isp h er ica H a ll o f th e U p p e r H e ld e rb e rg in N o r th A m erica , f ro m w h ich it can be d is tin g u ish ed read ily by its few er ribs. C. p roducto ida , is n o t m ere ly the g ero n tic stage o f C. ro b u sta w h ich also it closely resem bles. G ero n tic spec im ens o f th e la tte r a re equa lly obese b u t do n o t have the h igh um bonal a re a and recu rv ed beak o f C. p ro d u c to id a . M o reo v er, C. ro b u sta has a m esial sinus a t all s tages in its deve lopm ent, an d th e shell is no t so f la ttened on th e ca rd in a l ang les. I t is in te restin g to no te in th is species (a s a lso to certa in e x te n t in C. bozvieae) the a t ta in ­m en t o f a P ro d u c tu s -l ike fo rm .

C h o n e t e s (C h o n e t e s) g a s k i n i , s p . n o v .

{ P I . V I I I . , f ig . 9 . )

T y p e M a t e r i a l .— A v en tra l valve p re se rv ed in h a rd , b lu ish lim estone f ro m th e scarp a long O ld H u t C reek , B ind i D is tr ic t, G ippsland (see m ap, G ask in , 1943). T h e species is nam ed a f te r M r. A . J. G ask in , w ho co llected th e type spec im en, w h ich is now in th e U n iv e rs ity o f M e lb o u rne G eology D e p a rtm en t Museum (R eg . N o. 1913).

D e s c r i p t i o n .— V e n tra l valve 4 cm . w id e ; g re a te s t leng th p rese rv ed in ty p e spec im en (w h ich is in co m p le te ) 2 cm .; b u t a com plete valve w o u ld be lo n g e r; h e ig h t (d is tan ce pro file rises above p lane jo in in g a n te r io r an d p o s te r io r m a rg in s ) ab o u t 1 -25 cm. C ard in a l m arg in rises s ligh tly a t um bo, w hich is n o t p ro m in en t. O ne sp ine on ly p re se rv ed on th e ca rd in a l m arg in . I t is i cm . long , s tra ig h t, s ligh tly tu rn e d o u tw a rds , an d possessing fine an n u la tio n s (see ph o to m ic ro g rap h , PI. V I I I . , fig. 1 1 ). T h e va lve is f la ttened on th e ca rd in a l ex trem ities . T h e ex te rn a l o rn a m e n t consists o f 4 0 ribs w h ich a re m uch s tro n g e r in th e cen tre o f the shell th an th ey a re on th e ca rd in a l m arg ins. T h e ribs do n o t a ll com m ence a t th e um bo, som e beg in n in g a t locations a long th e ca rd in a l m arg in , th e fu r th e s t o u t s ta r t in g a t a p o in t 13 m m . f ro m th e um bo. T h e ribs in c ro ss-section fo rm low arches, an d th e in te rspaces a re ab o u t equal in w id th to th e ribs.

H o r i z o n .— B ind i L im esto n e (M id d le D e v o n ia n ).

C o m m e n t .— T h is la rg e new species i s p henom ena l fo r its possession o f an an n u la ted sp ine. I t is c learly n o t an a r te fa c t, n o r is it a sm all a n n u la te d shell like T e n ta c u l i te s re s tin g ag a in s t the ca rd in a l m arg in o f the C honetes. A s fa r as th e a u th o r is aw are , an a n n u la te d sp ine on a C h o n etes h as n o t been described be fo re .

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D i s c u s s i o n o f t h e G e n u s A n o p l i a .

F am ily C H O N E T ID A E H a ll an d C larke, 1895.

G enus A n o p l i a H a ll a n d C larke , 1892.

G en o h o lo ty p c 2 \ L e p ia e tu i n u c lea te , H a l l , 1857, 10 th R e p t. N e w Y o r k S ta te C a b in e t, p . 47 (q u o te d f r o m F o s s i l iu m C a ta lo g u s ) ■

E t y m o l o g y o f G e n e r i c N a m e .— G reek anop los = u narm ed .

D i a g n o s i s o f G e n u s .— Sm all choneto ids p o ssessing a sm oo th o r a lm ost sm ooth su rfa ce , b u t w ith o u t sp ines on th e v en tra l c a rd in a l m arg in . V e n tra l m ed ian sep tum , te rm in a tin g ab rup tly .

C o m m e n t .— A s fa r as th e a u th o r is aw are , on ly fo u r species h av e been re fe r re d to th is genus, v i z . :—

A n o p l ia n u c le a ta ( H a l l ) L o w e r a n d M id d le D e v o n ia n — O r is k a n y o f O n ta r io a n d N e w Y c r k . A m a z o n . O n o d a g a a n d G ra n d G rcv e (C a le y , 1 9 4 0 ). M id d le D e v o n ia n o f M a ry la n d . L o w e r De v o n ia n o f M o se l le (D a h m e r , 1928, 1 9 3 0 ).

A n o p l i a h e ld e r b e r g ia e . S c h u c h e r t . L o w e r D e v o n ia n — H e ld e r b e r g

F o rm a t io n .

A n o p l ia a u s t r a l i s . G i l l. L o w e r D e v o n ia n o f V ic to r ia Y e r in g ia n

S e r ie s .

A n o p l ia w i th e r s i G il l. D i t to .

W hen H a ll and C larke erec ted th e genus, th e absence o f sp ines w as re g a rd e d as its ch ief fe a tu re — hence th e nam e m ean ing “ u n a rm e d .” H o w ev er, A . he lderberg iae w as fo u n d to possess sp ines like C honetes, b u t S ch u ch e rt (1 9 1 3 ) has a rg u ed th a t th e genus is a good one to em brace “ th e ea rly sm ooth o r s ligh tly lam ellose, h igh ly convex , sm all choneto ids w ith a ven tra l m ed ian sep tu m .” T h e v en tra l m ed ian sep tu m is a com m on fe a tu re o f C honetes, an d th e V ic to r ia n fo rm s o f A n o p l ia a t least a re n o t h igh ly convex . S m o o th C h o n e tes a re a lso know n. T h u s , none o f the fe a tu re s nam ed by S ch u ch e rt can now be sa id to be ch a rac te r is tic o f A n o p l ia alone. T h e re seem s to be no cou rse le f t b u t to keep to th e o r ig in a l defin ition o f th e genu s as sm all, sm oo th choneto ids w ith o u t sp ines, an d re fe r A . he lderberg iae to C honetes. I t is in te re stin g to n o te th a t sm oo th fo rm s h av e a rise n tw ice in the C h o n etes line o f evo lu tion , v iz., A n o p l ia in th e L o w er D evon ian , an d sm ooth C ho n etes (C . g la b er) in th e U p p e r

C arb o n ife ro u s.. A n o p l ia possesses re v e rs io n a ry ch arac te rs . T h e te rm “ re v er­sion ” is h e re used in d is tin c tio n f ro m th e te rm atav ism , and as defined by C rew (1925 , p. 3 ) . I t m ay be assu m ed th a t th e g enus C h o n etes “ d eg enera ted ” in one d irec tion to A n o p lia , ju s t as in a n o th e r i t “ advanced ” to P ro d u c te l la an d P ro d u c tu s . T h e re v e rs io n a ry ch a rac te rs a re :—

(1 ) L oss o f o rn am en t.— T h e su r fa c e o f th e shells is sm oo th in A n o p lia , o r a lm ost so. S ch u ch e rt w r ites , “ T h e sm oo th fo rm s of C h o n e tes a re n o t descendan ts o f A n o p lia , b u t a re d e r iv ed fro n t

C ho n etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 143

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144 E d mu n d D . G ill:

assoc ia ted finely s tr ia te d fo rm s o f th e fo rm e r g en us .” A p p a ren tly bo th th e sm oo th C h o n etes an d A n o p l ia a ro se fro m finely s tr ia te d C h o n e tes b u t a t d if fe ren t tim es. H a ll (1892, P la te 15a, fig. 18) f igu res a spec im en o f A . nuc lea ta w ith fa in t r ibb ing w h ich m ay be re g a rd e d as an ind ica tio n o f th e o rn a me n t ca rr ied by its an cesto rs. A n ex am p le o f s im ila r genetic in te rest is a spec im en o f A . austra lis co llected by M r. R . B. W ith e rs in the K in g lak e D is tr ic t (P la te V I I I . , . fig. 4 ) .

(2 ) L oss o f Sp ines.— H a ll an d C larke m ade th is th e ch ie f d iagnostic c h a rac te r o f th e ir genus, an d it is indeed n o tab le am ong a w ho le series o f sp inose fo rm s w h ich w ere an im p o rtan t e lem ent in m arin e fau n as fo r o v er 150 m illion years. I t is n o tab le also fo r the reaso n th a t th e genera l ten d en cy w ith th e efflux ion o f t im e w as fo r th e increase an d no t decrease o f sp inosity .-

N o t e s o n S p e c i es P r e v i o u s l y D e s cr i b e d .

A n o p l i a a u s t r a l i s Gill.

A n o p l i a a u s t r a l i s G ill, 1942, pp . 38-39 , P I . IV ., f ig. 8.

T h is species is v e ry ch a rac te r is tic o f th e R u d d o c k ’s Q u a rry h o rizo n o f th e typ e Y erin g ian B eds a t L ilydale: I t occurs ing re a t n um b ers a t R u d d o ck s Q u a r ry a long w ith equa lly g re a t n u m b ers o f C h o n e tes ru d d o ck en s is , sp. nov ., and S tro p h e o d o n ta b ip a r tita (C h a p m a n ) . O n th e o th e r h and , it is ve ry ra re in the h ig h est beds o f th e series, on ly one spec im en h av ing been collected,^ fo r instance , f ro m H u l l- ro a d , M oo ro o lbark . T h e R u d d o c k ’s Q u a r ry h o rizo n has been traced so u th to Moo roo lbark , w here A . a u stra lis has been co llected f ro m a la rge c u tt in g on M an c h este r- ro ad n o r th o f the ra ilw ay s ta tion .

T h e tw o su b s id ia ry r idges in ad d it io n to th e m ed ian sep tu m a re o f in te re s t in th is species. C erta in para lle ls to th ese can be fo u n d in o th e r genera. F o r exam p le , S o w e rb y e lla g rac il is Jo n es (1928, p. 473, P la te X X IV ., fig. 2 2 ) possesses a s im ila r com p lem ent o f r id g e s ; also C ho n etes cu m b re n s is G arw o o d (1931 , p. 148).

F u r th e r O ccu rrences.— In ad d it io n to localities p reviou sly nam ed, A . a u stra lis has been co llected f ro m th e q u a r ry n o r th o f S ym e’s H o m estead , K il la ra (loc. 3 2 ) , an d f ro m Je ru sa le m C reek (G eo l. S u rv . V ic., R eg. N o. 18218).

A n o p l i a w i t h e r s i Gill.

A n o p l ia w i th e r s i G ill, 1942, p . 39, P I. I.V ., fig . 7.

U su a lly A . a u stra lis is th e d o m in an t fo rm w h e re b o th the V ic to r ia n species a re p resen t tog e ther. A n ex cep tion to th is has been no ted a t Je ru sa lem C reek , east o f E ild o n W e ir . T h e

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C hon etid a e f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 145

n u m b ers g iven w ith th e fo llow ing new reco rds o f o ccu rrence a re reg is te red n um bers o f th e G eological S u rv ey o f V ic to r ia :—

N os. 18222 an d 18223— ligh t faw n y -g rey san dsto n e from 70 cha ins S .E . o f the ju n c tio n o f Je ru sa lem an d B arnw e ll ’s C reeks, Jam ieson , Q .S .

N os. 18218 an d 18227, f ro m sp u r betw een W ilson ’s and B arnw e ll ’s C reeks.

V a r ia tio n s have been no ticed in A . w i th e r s i in th e leng th o f th e sep ta, in the p ro m inence o f th e beak, an d in the genera l ou tline o f the shell.

S t r a t i g r a p h i c a l C o n s i d e r a t io n s.

T h e earlies t re fe re n ce to chon e tid s in V ic to r ia is p robab ly th a t m ade by B landow sk i in 1855 w hen h e figu red som e u n desc rib ed fossils f ro m th e M c lv o r G oldfield . H is p la te opposite page 223, fig. 359, is ev id en tly a C honetes.

T h e nam ed species o f V ic to r ia n C h o n etes w ere described by M cC oy (1876). an d C hapm an (1 9 0 3 ) . T o these th e p re sen t w r i te r has ad d ed tw o species o f A n.op lia (1 9 4 2 ) , an d th e new species o f C ho n etes described in th is pap er. T h ese am o u n t to fo u r te e n cho n e tid species in all. M a te r ia l has been co llected w h ich ind icates th e p resence o f a n u m b er o f fu r th e r new species, bu t th e specim ens a re n o t good eno ug h on w h ich to fo u n d new species. T h e S ilu r ia n an d D ev o n ian ro c k s 'o f V ic to r ia a re rich in chonetids. Som e occu r in g a rg a n tu a n n u m b ers, e.g., C h o n etes ru d d o ch en s is , C. austra lis , and A n o p l ia a u s tr a l is; a lso to a less ex ten t, C. m e lb o u rn en sis , C. c ressw elli, and A . w ith e rs i.

Su b d i v i s i o n o f t h e Y e r i n g i a n Se r i e s i n t h e T y p e A r e a .

T h e V ic to r ia n chonetids a re good in d ex fossils. C. m e lb o u r ­nen s is is s tr ic tly M elbou rn ian , C. a u stra lis a n d C. g a sk in i s tr ic tly lim ited to th e B uchan an d B ind i B eds, an d th e re s t s tr ic t ly Y e rin g ian (L o w e r D e v o n ia n ). D iv is ions w ith in th e Y erin g ian S eries can be sa tis fac to r i ly m ade on th e basis o f these fossils, an d th e fo llow ing subd iv is ion is p ro po sed ( f o r s truc tu re , v id e G ill, 1942) :—

1. L o w e r Y e r i n g i a n — to be recogn ized by th e p resen ce o f C ho n etes ru d d o cken s is , A n o p l ia austra lis , an d S tr o p h e o- d o n ta b ipartita . ( I t has been no ted th a t th e re is a S tro p h e o d o n ta b ipa r tita in th e D evon ian beds o f N o rth A m erica (S w a r tz , 1941 ), b u t it belongs to L e p to s tro p h ia , w h ich sub-genus is now acco rded generic rank . A s o ur S . b ip a r tita belongs to S tro p h e o d o n ta sen su s tr ic to th e re is no need to change th e n a m e ) . T h ese a re all p ro lif ic form s, an d th e ir occu rrence in s tre n g th m ay be a lw ays tak en as an ind ica tion o f th e p resence o f th is sub-d iv is ion .

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146 E d mu n d D . G ill:

2. U p p e r Y e r i n g i a n — to be recogn ized by th e p resence o f C honetes cressw e lli, C. ro b u sta , an d C. k illa rensis.

T h ese subd iv is ions a re in keep ing w ith w h a t w e know o f the Y e rin g ian fau n u les as a w hole. O f course, such subdiv isions m u st be re g a rd e d as te n ta tiv e in th a t fu r th e r subd iv is ions w ill p rob ab ly becom e possib le as o u r know ledge o f these beds an d th e i r fau n u les increases. H o w ev er, th is d is tin c tio n betw een U p p e r an d L o w er Y e r in g ia n w ill help considerab ly in the c lassif ica tion o f s tra ta e lsew here in re la tio n to th e typ e L ilyda le beds. F o r instance, th e g rey m u d sto n e beds n o r th o f T o m m y ’s H u t w ith p len ti fu l 5 . b ipa rtita , an d th e b lu ish in d u ra te d m u d ­stones o f W est K ing lake w ith A . austra lis , the redd ish m udstones o f Y ellingbo w ith .S', b ip a r tita and C. cf. ru d d o ck en s is , th e g rey m u d sto n es a t C h ris tm as H il ls w ith S . b ipa rtita , an d s im ila r beds a t “ T w o m iles below S im m o n d ’s B rid g e H u t on th e Y ar ra ,” m ay all be classified as L o w e r Y e r in g ia n ; th e b lu ish -g rey m u d ston es a t K i l la ra (Iocs. 34 an d 35 ) m ay be c lassified as Up p e r Y erin g ian . T h e s tro n g affin ities betw een C. ta g g er tyen sis an d th e U p p e r Y erin g ian fo rm C. p s ilop lia suggests an U p p e r Y e rin g ian c lassif ication fo r th e beds in the B lue H il ls in w hich C. ta g g e r tye n s is occurs. N o C h o n etes h av e yet been described fro m th e H e a th co te B eds, b u t th e co llections m ade by D r. T h o m as h ave n o t yet been stud ied .

C h o n etes ru d d o c k e n s is an d S tro p h e o d o n ta b ip a r tita a re en tire ly ab se n t f ro m th e U p p e r Y e r in g ia n beds o f th e L ily da le D is tr ic t. O ne specim en on ly o f A n o p l ia austra lis has been fo u n d a t H u ll- ro ad , M o o ro o lb a rk (loc. 1 3 ), an d one on ly a t N o r th o f L ilydale (loc. 3 ) , w h ereas bo th species a re p ro lif ic in th e L o w e r Y ering ian . A s fa r as o u r know ledge goes, any o f th e th re e fo rms n am ed as c h a rac te r is t ic o f the L o w er Y ering ian , i f p re sen t in s tren g th , m ay be tak en as ind ica tive o f a L o w er Y e r in g ia n ho rizon . T h e th re e fo rm s g iven as ch a rac te ris tic o f th e U p p e r Y er in g ia n have n o t been fo u n d o u ts id e th o se beds, so a p p a ren tly any o f th e th ree species, if p re sen t a t all, is an in d ica tio n o f th at ho rizon .

R u d d o c k ’s Q u a r ry (loc. 2 0 ) is nam ed as th e ty p e locality fo r th e L o w er Y erin g ian . T h e o live-g rey in d u ra te d m ud sto nes (w ith occasional still h a rd e r sand ston e b a n d s) fo u n d th e re can be t ra c e d f ro m M o o ro o lb a rk th ro u g h th e R u d d o c k ’s Q u a r ry a rea (w h e re p itch affec ts th e s t r ik e ) , an d n o r th to w ard s Y a r ra G len. H u ll- ro a d , L ilyda le (loc. 1 ) , is n am ed as th e ty p e locality fo r the U p p e r Y erin g ian . T h e re , in w h itish an d red d ish so f t m udstones,C. ro b u s ta an d C. c ressw e ll i have been co llected, an d C. k il la ren s is occu rs in the ad ja c e n t loca lity o f M e lb o u rn e H il l, L ilyda le ( loc. 7 ) .

T h e J o r d a n i a n Se r i e s .— T h e n e x t qu estio n is th e re la tio n o f th ese fo rm s to the Jo rd a n ia n S eries (G ill, 1 94 1 ). Ex c e p t fo r a few u b iqu itou s fo rm s, th e fa u n as o f th e M e lb o u rn ian and

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C h onetidae f r o m th e P a laeozo ic R o c k s o f V ic to r ia . 147

Y e rin g ian a re m u tu a lly exc lusive , a lth o u g h th ey a re bo th o f l i t to ra l fac ies. T h e re w ou ld n o t be th is fa u n a l b reak if the tw o series co n stitu te d a co n tinu u m in tim e. T h e re m u st be a tim e- b reak betw een th e tw o series, an d th is is occup ied by th e J o rd a n ia n Series. T h is series (as know n a t p re se n t) is pelag ic, b u t n o t ju s t th e pe lag ic facies o f a p a r t o f th e M elb o u rn ian or Y erin g ian . L i t to ra l fo rm s a re ra re in th e Jo rd a n ia n, and so •chonetids a re n o t to be expected . A b rach ia l v a lve w h ich m ay be .a C ho n etes (co llec ted by D r. I. Cookson. a t M cM ah o n ’s C reek ) is the on ly cho n e tid fo u n d so fa r in th e series.

T h e M e lb o u rn ian beds con ta in g rap to lites o f L o w er Lud low a g e (Jo n e s, 1927). T h e Y e r in g ia n beds a re L o w er D evon ian (G ill, 1942 ), an d m ay even ex ten d up in to th e M idd le D evon ian (R ip p e r, 1938, H il l , 1939, 1943). T h u s th e re is a lacu na o f U p p e r L ud lo w age, w h ich m u st be th e age o f th e Jo rda n ia n beds. _A P o s id o n o m ya com m on a t M cM a h o n ’s C reek (e a s t o f W arb u r- ~ton) is v e ry s im ila r to P . eu g y ra f rom etage E . o f B ohem ia, w h ich is eq u iv a len t to th e U p p e r L ud low .

C o r r e l a t i o n w i t h O v e r s e a s D e p o s i t s . —T h e re a re in te restin g para lle ls betw een th e V ic to r ia n chonetids a n d fo rm s described fro m the classic series o f E u ro p e an d N o r th A m er ic a; also f ro m beds in Indoch ina . T h ese m ay be su m m arized as fo l low s :—

S t r a t ig r a p h i c a l p o s i t io n in

V ic t o r ia .

V ic to r ia nS p e c ie s .

O v e r s e a sS p e c ie s .

S t r a t i g r a p h i c a l p o s i t io n O v e r s e a s .

tM e lb o u r n i a n . . C h o n e te s m e lb o u r n e n s is C . n o v a s c o t ic a o f N th .

A m e r i c a a n d E u r o p eL u d lo w .

Y e r in g ia n

Y e r in g ia n

C . p r o d n c to id a

C . c r e s s w e l l i

C . h e m is p h e r i c a o f N th . A m e r i c a . C . v e r n e u l i o f E u r o p e

C . tncm g 'pcfen s'is o f I n d o c h in a

C . s e t i g e r a o f N th .A m e r ic a

C . s o r o r a n d C . C. e m b r y o o f E u r o p e

U p p e r H e ld e r b e r g , e tc .

( L o w e r ) D e v o n ia n

'Y e r in g ia n C . r u d d o c k e n s i s M a r c e l lu s -W a v e r le y

'Y e r i n g ia n C . ta g g e r t y e n s is C . s a r c in u la ta

C . u n k e le n s i s

L o w e r D e v o n ia n , “ m o s t a b u n d a n t in t h e U p p e r S ie - g e n ia n . ”

U p p e r m o s t L . D e v .

" Y e r in g ia n A n o p l i a a u s t r a l i s

C . m a o r ia

A . n u c lc a ta

L o w e r D e v o n ia n o i N .Z . , “ S ie g e n ia n ot L o w e r C o b le n z ia n .”

L . D e v . o f M o s e l le ; O r i s k a n y a n d O n o iv d a g a o f N th . A m e r i c a .

I t shou ld be no ted th a t th e above com p arison s a re no t all o f ■ equal value. C. m e lb o u rn e n s is an d . C. n o va sco tica a re very s im i la r ; so also a re C. ta g g e r tyen sis , C. m aoria , an d C. sa rc in u ­la ta . O n th e o th e r han d , the co m parisons-betw een C. ru d d o c k e n s is -and C. setigera , an d betw een C. p ro d u c to id a an d C. h em isp h er ica , a re based on s tr ik in g likenesses in ex te rn a l fo rm . In bo th the •cases quo ted th e im p o rta n t in te rn a l ch a rac te rs a re n o t know n.

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148 E d mu n d D . G ill:

F u r th e r , th e re is no g re a t likeness betw een o u r species o f A n o p l ia a n d A . nuc lea ta , b u t as th e gen us is so ra re in n u m b er o f species, th e re is no d ou b t sign ificance in its p resence.

T h e L ilyda le B eds, w h ich co n stitu te th e ty p e beds of th e Y e r in g ia n S eries, a re v e ry th ick . A lth o u g h th e th ickn ess a lre ad y g iven on th e ev idence ava ilab le (G ill, 1942) w ill very likely be red u ced as o u r know ledge o f th e s tru c tu re is increased , th e re n everth e less is certa in ly a g re a t th ickness o f beds invo lved. I t is possib le th a t th e m u d sto n es and sand sto nes o f th e Yerin g ian S eries cover the w hole o f L o w er D evon ian tim e, b u t a g re a t th ickn ess o f beds below th e R u d d o c k ’s Q u a rry h o rizon is ap p a ren tly qu ite u n fo ss i l i fe ro u s , an d the l im its o f th e series have n o t y e t been p rec ise ly defined. T h e w r i te r p re fe rs to w a it till th e fau nu les o f th e Y e r in g ia n type a re a have been fu r th e r w o rked ou t, b e fo re d ra w in g an y close co rre la tio n s w ith th e c lassic o v e r­seas series.

A c k n o w l e d g m e n ts .

T h e a u th o r w ishes to ex p ress h is a p p rec ia tio n o f the k ind co -o pera tion o f the U n iv e rs ity o f M e lbo u rn e D e p a rtmen t o f G eology ( th ro u g h P ro fe sso r E . S. H il ls an d D r. F . A . S in g le to n ) , th e N atio na l M u seu m ( th ro u g h the la te M r. D . J . M ahony , D ire c to r, and th e pa laeon to log ist, M r. R . A . K e b le ), an d th e G eological S u rv ey o f V ic to r ia ( th ro u g h th e D ire c to r, M r. W . B a ra gw an a th ) . T h e p h o to g rap h s w ere taken by M r. L . A. B aillo t, o f th e M e lbo u rn e T echn ica l College.

R e f e r e n c es .

A l l a n , R . S , 1935.— T h e F a u n a o f th e R e e f to n B e d s ( D e v o n ia n) , N e w Z e a la n d . N . Z . G e o l S u r v . P a l. B u l l . 14.

B e e c h e r , C. E , 1898.— T h e O r ig in a n d S ig n i f ic a n c e o f S p in e s . A S tu d y in E v o lu t io n . A m e r . J o u r n . S c . , -9 th se r ie s , V o l . V I .

B l a n d o w s k i, W „ 1855.— A D e sc r ip t io n o f F o s s i l A n im a lc u la e in P r im i t iv e R o c k s f ro m th e U p p e r Y a r r a ( p la te o p p o s i te , p . 2 2 3 ). T r a n s . P h i l , I n s t . V ic ., v o l. I ., pp . 221-223.

B r e g e r , C . L , 1906.— O n E o d e v o n a r ia , a n e w s u b -g e n u s o f C h o n e te s . A m e r . J o u r n . S c ., v o l. X X I I , pp . 534-536.

C a l e y , J . F , 1 9 4 0 — P a la e o z o ic G e o lo g y o f th e T o r o n to — H a m i l to n A re a ,. O n ta r io . M em . 224, G eo l. S u rv . C a n a d a , O t ta w a .

C h a p m a n , F , 1903.— N e w o r L i t t le -K n o w n V ic to r ia n F o s s i ls in th e N a t io n a l M u se u m , M e lb o u rn e . P t . 1. S o m e P a la e o z o ic S p e c ie s . P r o c . R o y . S o c . V ic . V o l. X V . ( 2 ) , n . s , pp . 104-122.

---------------- , 1914.— O n th e P a la e o n to lo g y o f th e S i lu r ia n o f V icto r ia . A u s t .A s s o c . A d v . S c ., v o l. X I V , pp . 207-235.

C l a r k e , J . M , 1907.— S o m e N e w D e v o n ic F o s s i ls . N e w Y o r k S t a te M u s e u m B u l l . 107, p p . 153-291.

C o u c h m a n , A , 1877.— R e p o r t o f P r o g r e s s , G e o l. S u rv . V i c , p. 16.

C r e w , F A . E , 1925.— A n im a l G e n e t ic s E d in b u rg h a n d L o n d o n .

D a h m e r , G , 1928.—W a re n H u n s r i ic k u n d T a u n a z u r d e r W en d e U n te r d e v o n— M it te ld e v o n L a n d ? J a k r b . p r e u s s . g e o l. L . - A . f . 1928 49, pp . 1152-1162.

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D a h m e h , G , 1 9 3 0 — M a n d e ln e r S c h ic h te n (Z w e is c h a le r f a z ie s d e s o b e rs te n U n te rd e v o n s ) a n d e r M o se l. Z u g le ic h e in B e i t r a g z u r K e n n t n i s d e r

P h i l h e d r a - a r t tn im rh e in is c h e n D e v o n . J a h r . P r e u s s . G eo l, L a n d . , pp . 88-94.

---------------- , 1936.— D ie F a u n a d e r S ie g e n e r S c h ic h te n v o n U n k e l (B l .K o n ig s w ir i te r ) . J a h r . - P r e u s s . g e o l. L . - A . 56, p p . 633-671.

-— :----------- , 1937.— D ie F a u n a d e r S ie g e n e r S c h ic h te n im A h rg e b ie t . J a h r .p r e u s s . g e o l. L a n d . , B a n d 57, H e f t 1, pp . 435-464.

D e K o n i n c k , L ., 1847.— R e c h e rc h e s s u r le s A n im a u x F o s s i le s , p t . 1. M o n o g ra p h ic d e s G e n re s P r o d u c tu s e t C h o n e te s , L ie g e .

G a r w o o d , E . J . , 1931.— T h e T u e d ia n B e d s o f N o r th e r n C u m b e r la n d a n d R o x b u r g h s h i r e E a s t o f th e L id d e l W a te r . Q u a r t . J o u r n . G e o l. S o c ., L X X X V I I . , p t. 1, pp . 97-159 .

G a s k i n , A . J . , 1943.— T h e G e o lo g y o f B in d i, V ic to r ia . P r o c . R o y . S o c . V ic . V o l. L V „ p t. 1, n . s , pp . 81-108.

G i l l , E . D ., 1940.— T h e S i lu r ia n R o c k s o f M e lb o u rn e a n d L i l y da le : A D is c u s s io n o f th e M e lb o u rn ia n -Y e r in g ia n B o u n d a ry a nd A s s o c ia te d P ro b le m s . P r o c . R o y . S o c . V ic ., L I I , p t. 2, n .s ., pp . 249-261.

----------------> 1942.— T h e T h ic k n e s s a n d A g e o f th e T y p e Y e r in g ia n S t r a ta ,L i ly d a le , V ic to r ia . P r o c . R o y . S o c . V ic ., v o l. L I V . , p t. 1 n .s., pp . 21-52.

---------------- ,1 9 4 4 .— T r i lo b i ta o f th e F a m i ly C a ly m e n id a e f r o m V icto r ia .P r o c . R o y . S o c . V ic . , v o l. L V I . , p t. 2, n .s . I n p re ss .

G r a b a u , A . W ., a n d S h i m e r , H . W , 1909.—N o r th A m e r ic a n I n d e x F o s s i ls . N e w Y o rk .

H a l l , J . a n d C l a r k e , J . M ., 1892.—P a la e o n to lo g y o f N e w Y o rk , v o l. 8, p t. 1.

H i l l , D ., 1 9 3 9 — T h e D e v o n ia n R u g o s e C o ra ls o f L i ly d a le a n d L o y o la , V ic to r ia . P r o c . R o y . S o c . V ic . , v o l. L I . , p t. 2, pp . 219-264.

__________, 1943.— A R e - I n te r p r e ta t i o n o f th e A u s t r a l ia n P a la e o z o ic R e c o rd ,b a se d o n a S tu d y o f th e R u g o s e C o ra ls . P r o c . R o y . S o c . Q u e e n s la n d , vo l. L I V . , N o . 6 , p p . 53-66.

H i l l s , E . S . , 1 9 2 9 — T h e G e o lo g y a n d P a la e o n to lo g y o f th e C a th e d ra l R a n g e a n d B lu e H i l l s in N .W . G ip p s la n d . P r o c . R o y . S o c . V ic , v o l. X L I . ,

p t. 2 , pp . 176-201.

J o n e s , O . A ., 1927.— S i lu r ia n G ra p to l i te s f r o m S tu d le y P a r k , M e lb o u rn e , A u s tra l ia . G e o l. M a g ., 64, p p . 101-105.

J o n e s , O . T . , 1928.—P le c ta m b o n i te s a n d S o m e A l l ie d G e n e ra . M e m . G eo l, S u r v . G t. B r i ta in , P a la e o n to lo g y , v o l. I . , p t. 5, pp . 367-527.

M a n s u y , H ., 1916.— F a u n e s P a le o z o 'iq u e s d u T o n k in s e p te n t r ion a l . M e m . S e r v . G e o l. In d o c h in e , v o l. V ., f a s c . iv ., pp . 1-23.

__________, 1919.— D e s c r ip t io n d e Q u e lq u e s E s p e c e s d u D e v o n ie n d u T o n k in ,d u L a o s , e t d u C a rb o n i f e re n d u Y u n n a n . M e m . S e r v . G e o l . I n d o c h in e ,

v o l. V I , fa sc . 1, pp . 21-33.

__________f 1921.— D e s c r ip t io n d e F o s s i le s d e s te r r a in s P a le o zo iq u e s e tM e so z o iq u e s d u T o n k in S e p te n tr io n a l . M e m , S e r v . G e o l. I n d o c h in e , v o l. V I I I , fa sc . 1, pp . 11-27.

M c C o y , F , 1 8 7 6 — P ro d ro m u s o f th e P a la e o n to lo g y o f V ic to r ia , D e c a d e IV . ,

G eo l. S u rv . V ic .

M c L e a r n , F . H , 1 9 2 4 —P a la e o n to lo g y o f th e S i lu r ia n R o c k s o f A r is a ig , N o v a S c o t ia . M e m . 137, G eo l. S u rv . C a n a d a .

P a e c k e l m a n n , W , 1930.— D ie B ra c h io p o d e n d e s d e u ts c h e n U n te r k a rb o n s.1. D ie O r th id e n , S t r o p h o m e n id e n , u n d C h o n e te n d e s Mi t te le r e n u n d O b e re n U n te r k a r b o n s . A b h . p r e u s s . g e o l. l a n d e n s a n s t . , N .F . 122.

P a t t e E 1926.— E tu d e s P a le o n to lo g iq u e s R e la t iv e s a la G e o lo g ie d e L ’E s t d u ’T o n k in (P a le o z o 'iq u e e t T r i a s ) . B u l l , S e r v . G e o l. In d o c h in e ,

v o l. X V , fa s c . 1, pp . 1-241.

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150 E d mu n d D . G ill:

P r e n d e r g a s t , K . L , 1944.— P e r m ia n P ro d u c t in a e a n d S tro p h a lo s i in a e o f W e s te r n A u s t r a l ia . J o u r . R o y . S o c . W e s t e r n A u s t r a l ia , v o l. X X V I I I . r pp . 1-74.

R a y m o n d , P . E , 1939.— P r e h is to r ic L i t e . C a m b r id g e , U .S .A .-

R e e d , F . R . C , 1917.— T h e O rd o v ic ia n a n d S i lu r ia n B ra c h io p o d a o f the- G irv a n D is t r ic t . T r a n s . R o y . S o c . E d in b u r g h , v o l. L I . , p t. 4, p p 795-998.

---------------- , 1921.— N o te s o n th e L o w e r D e v o n ia n B e d s o f T o rq u a y, p t. I I ,B ra c h io p o d a . G e o l. M a g ., v o l. L V I I I , pp . 313-324.

R i p p e r , E . A , 1 9 3 8 — N o te s o n th e M id d le P a le o z o ic S t ro m a to p o ro id F a u n a s o f V ic to r ia . P r o c . R o y . S o c . V ic . , v o l. L , p t. 2, n .s . pp . 221-243.

S c h u c h e r t , C , 1913.— S e c tio n o n th e B ra c h io p o d a in th e Z i t te l -Ea s tm a n - T e x tb o o k o f P a la e o n to lo g y . L o n d o n .

S c h u c h e r t , C. a n d L e V e n e , C . M ., 1929.— F o s s i l iu m C a ta lo g u s , ed.. J . F . P o m p e c k j , v o l. 42, B ra c h io p o d a .

S h i r l e y , J , 1 9 3 8 .— T h e F a u n a o f th e B a to n R iv e r B e d s (D e v o n ia n ) N e w ' Z e a la n d . Q .J .G .S ., v o l. X C I V , pp . 4 5 9 - 5 0 6 .

S h e r r a r d , K „ a n d K e b l e , R . A , 1937.— T h e O c c u r re n c e o f G ra p to l i te s n e a r Y a ss , N .S .W , P r o c . L in n . S o c . N . S .W . , v o l. L X I I , pp . 303-314.

S t r a w , S . H , 1932.— T h e F a u n a o f th e P a la e o z o ic R o c k s o f th e L itt le - M iss e n d e n B o r in g . S u m . o f P r o g r e s s , G e o l. S u r v . G t. B r i t . 1932, p t. 2, pp . 112-142.

S w a r t z , C. K , a n d F . M , 1941.— E a r l y D e v o n ia n a n d L a te S i lu r ia n F o r ­m a t io n s o f S o u th -e a s te rn P e n n s y lv a n ia . B u l l . G e o l. S o c . A m e r v o l. 52, N o . 8, pp . 1129-1192.

T h o m a s , D . E , 1937.— S o m e N o te s o n th e S i lu r ia n R o c k s o f th e H e a th c o te -A re a . M in . a n d G eo l. J o u r n ., v o l. 1, p t. 1. pp . 64-67.

D e s cr i p t i o n o f P l a t e .

P l a t e V I I I .

( N o p h o to g r a p h s a r e re to u c h e d .)

F i g . 1 .— C h o n e te s b o w ie a e , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( s y n ty p e ) X 2 a p p r o x -

F i g . 2 .— -C h o n e te s b o w ie a e , sp . n o v . , e x t e r n a l m o u ld o f v e n t r a l v a lv e ( s y n t y p e) sam e - s iz e a p p r o x .

F i g . 3 .— C h o n e te s p r o d u c to id a , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( h y p o ty p e) .X 3 .5 a p p r o x .

F i g . 4 .— A n o p l ia a u s t r a l i s G i l l . S p e c im e n f r o m K in g la k e s h o w in g r ib b in g ( e n l ar g e d ) .

F i g . 5 .— S p in e s o f C h o n e te s c r e s s w e lU C h a p m a n . S p e c im e n f r o m H u l l * r o a d , L i ly d a le . .

F i g . 6 .— C h o n e te s ta g g e r t y e n s i s , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( p a r a t y p e) X 2 a p p r o x .

F i g . 7 .— C h o n e te s p r o d u c to i d a , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( h o lo ty p e) X 1 -5 ’ a p p r o x .

F i g . 8 .— C h o n e te s t a g g e r t y e n s i s , sp . n o v ., i n t e r n a l c a s t o f v e n t r a l v a l v e ( s y n t y p e ) X 2 ' a p p r o x .

F i g . 9 .— C h o n e te s g a s k im , s p . n o v . , v e n t r a l v a l v e ( h o lo t y p e ) , s a m e s iz e . N o te s p in e ..

F i g . 1 0 .— C h o n e te s r u d d o c k e n s i s , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( h o lo ty p e) X 4a p p r o x . N o te lo n g s p in e .

F i g . 1 1 .— P h o to m ic r o g r a p h o f s p in e o f C h o n e te s g a s k in i , sp . n o v . ( v i d e f ig . 9 ) . N o te - a n n u la t i o n w h e r e s p in e j o i n t s . s h e l l , a n d a s e r ie s o f a n n u l a t i o n s a t t h e o u te r e n d .

F i g . 1 2 .— C h o n e te s p r o d u c to id a , s p . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e ( h o lo ty p e). s h o w in g s p in e b a s e s a n d m e d iu m s e p tu m .

F i g . 1 3 .— C h o n e te s ta g g e i ' t y e n s i s , s p . n o v . , e x t e r n a l m o u ld ( s y n ty p e ) s h o w in g e x te r n al o r n a m e n t , X 2 a p p r o x .

F i g . 1 4 .— C h o n e te s k i l l a r e n s is , s p . n o v . , i n t e r n a l c a s t , o f .v e n t r a l v a l v e (h o lo typ e ) X 2 ' a p p r o x .

F i g . I S .— C h o n e te s p s i lo p l ia , sp . n o v . , i n t e r n a l c a s t o f v e n t r a l v a lv e (h o lo ty p e) X 41 a p p r o x .

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P k o c . R o y . S o c . V i c t o r i a , 57 ( 1—2) , 1945. P l a t e V I I I .

Ch o n e te s an d An o p lia .

3551/45. [P a g e 1 5 1 .]