I I I I I I |ll I

V o L L X X V I I I . No. 309. ! PA2T I .

T H E I QUARTERLY JOURNAL

OY 'rHZ

GEOLOGICAL SOCIETY. ~,.._

EDITED BY

THE PERMAEENT SECRETARY.

MARCH ,~iS~, 1922.

LONDON :

LONGMANS, GREEN, AND CO. P

I'ARIB:--CHARLES KLINCKSIEOI~ 11 R U E D E L I L L E .

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LIST OF THE OFFICERS AND COUNCIL OF THE

GEOLOGICAL St)CIETY OF LONDON. Elected February 17th, 1922.

~r~i~rnt. Prof. A. C. Seward, Se.D., F.R.S., F.L.S

Prof. Edmund Johnston Garwood, M.A.,I George Thurland Prior, M.A., D.Sc., Se.D., F.R.S. [ F.R.S.

Richard Dixon Oldham, F.R.S. Herbert Henry Thomas, M.A., Sc.D.

~ e c r , t a r i t ~ . Walter Campbell Smith, M.C., M.A. I James Archibald Douglas, M.A., B.Sc,

~argign ~eeretarp. II~rra~urtr. SirArehibald Geikie, O.M., K.C.B., D.C.L., / Robert St~nstleld Herries, M.A.

Ida.D, So.D, F.R.S. }

Frederick Noel Asheroft, M.A., F.C.S. Prof. Owen Thomas Jones, M.A., D.Sc. Francis Arthur Bather, M.A., D.Sc., F.R.S, William Bernard Robinson King, O.B.E., Prof. Percy George Hamnall Boswell M.A.

O.B.E., D.Sc. Prof. William S~ Boulton. D.Sc., Assoc

R.C.Sc. Thomas Crosbee Cantrill, B.Sc. James Archibald Douglas, M.A., B.Sc. John Smith Flett, O.B.E., M.A., LL.D.

D.Sc., M.B., F.R.S. Prof. Edmund Johnston Garwood, M.A.,

Se.D., F.R.S. Sir Archibald Geikie, O.]K., K.C.B.,D.C.L.,

LL.D., Se.D., F.R.S. John Frederick Norman Green, B.A. Frederick Henry Hatch, O.B.E.. Ph.D. Robert Stansfield Herries, M.A.

Richard Dixon Oldham, F.R.S. George Thurla~ad Prior, I~I.A., D.Sc.,

FR;s. Prof. Sidney Hugh Reynolds, M.A., So.D. Prof. Albert Charl0s Seward, Sc.D.,

F.R.S., F.L.S. Walter Campbell Smith, M.C., M.A. Sir Aixbrey Strahan, K.B.E., Se.D., LL.D.,

F.R.S. Herbert Henry Thomas, l~.A., Sc.D. Prof. William Whitehead Watts, ]K.A.,

Sc.D., LL.D., F.R.S. Henry Woods, ]YLA., F.R.S.

~rrmancnt ~ tcr~tar!~. L. L. Belinfante, M.Sc.

~ibrarian. ~?l~rtt. Arthur Greig. M. St. John Hope.

STANDING PUBLICATION COMMITTEE. P~of. A. C. Seward, President.

Mr. W. Campbell Smith. Mr. J. A. Douglas. ) Secretaries. Mr. R. S. Herries, Treasurer.

Prof. P. G. H. Boswell. Dr. F. H. Hatch. Sir Aubrey Strahan. Prof. W. S. Boulton. Prof. O. T. Jones. Dr. H. H. Thomas. Dr. J. S. Flett. Mr. R, D. Oldham. Prof. W. W. Watts. Prof. E. J. Garwood. Dr. G. T. Prior. Mr. H. Woods. Mr. J. F. N. Green. Prof. S. H. Reynolds.

O R D I N A R Y M E E T I N G S O F T H E G E O L O Q I C A L S O C I E T ~ r TO BE HELD AT BURLINGT0t~ HOUSE.

SEssio~r 1 9 2 1 - 1 9 2 2 . 1922.

Wech~esday, April ............................. 12 ,, May ............................. 10 ~ - 24

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[ Bus~ne~s wi~ commence at 5.30 p.m. precisely.] The asterisks denote the dates on which the Council will meet.

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Q U A R T E R L Y J O U R N A L (Vols. I II to LXXVII, inclusive). Price to Fellows, ~£1 0s, 0d. each : ~£I 5s. 0d. in cloth. [Postage ls.] Separate parts (2, 5, 7, 9, 55, & 273 are out of print) 7s. 6d. each : price to Fellows 5s. [Postage 5d.]

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T H E GEOLOGY OF N E W Z E A L A N D . Translated by Dr. C. F. FISCH]~R from the works of MNI. HOCHSTETTE]~ & PETER~ANI~. Wit~ an Atlas of Siz Maps. Price 10s. net. [Postage 9d.]

CONTENTS.

Pages Proceedings of the Geological Society, Session 1921-22 .... . . . . . . . . . . . . . . . . . . . . lxix-lxxv

PAPERS READ. Page

2. Mr. E. B. Bailey on the Structure of the South-West Highlands of Scotland (Plate I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

3. Miss G. L. Elles on the Bala Country: its Structure and Rock-Succession (Plate II) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132

4. Dr. L. J. Wills & Mr. B. Smith on th~ Lower PalEeozoie Rocks of the Llangollen District (Plates III-V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

5. Mr, F. S.' Wallis on the Avonian of Broadfield Down [Abstract] ............ 227

[The Editor of the Quarterly Journal is directed to make it known to the Public that the A u t h o r s a lone a re r e s p o n s i b l e for t h e f a c t p ~ n d op in ions c o n t a i n e d in t h e i r r e s p e c t i v e Pape r s . ]

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__-._

6 - JUL 19~

V o L L X X V r [ L N o . 3 1 0 . PAnT 2.

T H E

QUARTERLY JOURNAL

OF T H E

GEOLOGICAL SOCIETY.

E D I T E D BY

THE PERMANENT SECRETARY

JULX 4~h, 1922.

[With Five Plates, illustrating Papers by Mr. E. B. Bailey, Miss G. L. Elles, and Dr. L. J. Wills & Mr. B~ Smith.]

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LIST OF THE OFFICERS AND COUNCIL OF THE

GE()I OGICAL S()CIETY OF LON DON. Elected Fe]a'ruary ~l~7~th, 1922.

~re~i~tnt. Prof. Albert Charles Seward, Sc.D., F.R.S., F.L.S.

¢~itt:~t't~i~tnt~. Prof. Edmund Johnston Garwood, M.A.,~ George Thurland Prior, M.A., D.Se.,

Sc,D., F.R.S. t F.t~.S. Richard Dixon Oldham, F.R.S. Herbert Henry Thomas, i~I.A., Sc.D.

~ ttrttartt~;. Walter Campbell Smith, M.C., M.A. t James Archibald Douglas, M.A., B.Se.

~orttgn bttrttarp. ~rta~ttrtr. SirArchibald Geikie, 0.M., K.C.B., D.C.L., I Robert Stansfield Herries, M.A.

LL.D., Se.D., F.I~.S. t

Frederick Noel Ashcroft, M.A., F.C.S. Francis Arthur Bather, M.A., D.Se., F.R.S. ProL Percy George Hamnall Boswell

O.B.E., D.Se. Prof. William S. Boulton, D.Sc., Assoc

Roy. Coll. Sci. Thomas Crosbee Cantrill, B.Sc. James Archibald Douglas, M.A., B.Sc. John Smith Flett , O.B.E., M.A., LL.D.:

D.Sc., M.B., F.Id.S. Prof. Edmund Johnston Garwood, M.A.,

Se.D., F.ILS. Sir Archibald Geikie, O.M., K.C.B., D.C:L.,

LL.D., Sc.D., F.I~.S. John Frederick Norman Green, B.A. Frederick Henry Hatch, O.B.E., Ph.D. Robert Stansfie!d Herries, M.A.

Prof. Owen Thomas Jones, M.A., D.Se. William Bernard Robinson King, O.B.E.,

M.A. Richard Dixon Oldham, F.R.S. z George Thurland Prior, M.4., D.Sc.,

F.R.S. Prof. Sidney Hugh Reynolds, M.A.. Sc.D. Prof. Albert Charles Seward, Sc.D.,

F.R.S., F.L.S. Walter Campbell Smith. M.C., M.A. Sir Aubrey Strahan, K.B.E., Sc.D., LL.D.,

F.I¢.S. Herbert Henry Thomas, M.A., Sc.D. Prof. William Whitehead Watts , M.A.,

Sc.D.. LL.D., F.l~.S. Henry Woods, M.A., F.E.S.

|Ptrmantnt ~ttrttarp. L. L. Belinfante, M.Sc.

I/.ibrarian. ~ltrh. Arthur Greig. M. St. John Hope.

S ~ A N D I N G P U B L I C A T I O N C O M M I T T E E . Prof. A. C. Seward, Pres iden t .

Mr. W. Campbell Smith. } Secretaries . Mr. R. S. Herries, Treasurer . Mr. J. A. Douglas.

Prof. P. G. H. Boswell. Dr. F; H. Hatch. Sir Aubrey Strahan. Prof. W. S. Boulton. Prof. O. T. Jones. Dr. H. H. Thomas. Dr. J. S. Flett. Mr. R. D. Oldham. Prof. W. W. Watts. Prof. E . J. Garwood. Dr. G. T. Prior. Mr. H. Woods. Mr. J. F. N. Green. Prof. S. H. Reynolds.

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SESSION 1922 -1923. 1922.

Wednesday, November ... . . . . . . . . . . . . . . . . . . . 8~---22 , , December . . . . . . . . . . . . . . . . . . . . . 6 - -20 a

1923. Wednesday, January . . . . . . . . . . . . . . . . . . . . . . . . 10#--24 #

,, ( A n n i v e r s a r y , Friday, Feb. 16th) February ...... 7a--28 ~*

,, March . . . . . . . . . . . . . . . . . . . . . . 1 4 - - 2 8 ~ ,, April . . . . . . . . . . . . . . . . . . . . . . . . . 18 a ,, May . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 -- 16 a

June . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 - -20 a The asf, erisks denote the dates on which the Council will meet.

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Q U A R T E R L Y J O U R N A L (Vols. III to LXXVII, inclusive). Price to Fellows, ~1 0s. 0d. each .. ~£1 5s. 0d. in cloth. [Postage Is.] Separate parts (2, 5, 7, 9, 55, & 273 are out of print) 7s. 6d. each • price to Fellows 5s. [Postage 5d.]

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G E O L O G I C A L L I T E R A T U R E added to the Geological Society's Librar 7 duringthe years ended December 31st, 1894-1913 and 1920, 1921. Price 58. each. To Fellows, 3e. 9d. each. [Postage 7d.] (Nos. 8 & 14 are out of print.)

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T H E G E O L O G Y O F N E W Z E A L A N D . Translated by Dr. C. F. FISCHER from the works of MM. HOCHSTETTER & PETERSIANN. With an Atlas of Six Maps. Price 10s. net. [Postage 9d.]

CONTENTS.

Pages Proceedings of the Geological Society, Session 1921-22, including the Pro-

ceedings at the Annual General Meeting, the President's Annlversary

Address, ere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i-lxviii

PAPER READ. Page

1. Mr. G. W. Lamplugh on the Junction of Ganlt and Lower Greensand near

Leighton Buzzard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

[The Editor of the Quarterly Journal is directed to make it known to the Public that the Au tho r s a lone are respons ib le for the fac t s and opinions con ta ined in t]aeir r e spec t ive Papers.]

e~# The Council request that all communications intended for publication by the Society shall be clearly and legibly written on one side of the paper only, wi th proper re fe rences , and in all r e spec t s in f i t cond i t ion for being , t once p laced in the P r i n t e r ' s hands. Unless this is done, it will be in tdae discretion of the Officers to return the communication to the Author for revision,

The Library at the Apartments of the Society is open every Week Day from Ten o'clock until Five, except on Saturdays (when the hours are from 10 to 1), and except during the fortnight commencing on the first Monday in September, when the Library is closed for the purpose of cleaning.

Fel lows are r e m i n d e d t h a t t hey a re no t en t i t l ed to receive t he Qua r t e r ly J o u r n a l r e g u l a r l y , unless a subscr ip t ion a t the r a t e of los. per volume is pa id in advance. Those Fel lows who do not r equ i r e the complete series can ob ta in s epa ra t e pa r t s a t the pr ice of 3s. each, i f appl ied for w i t h i n one yea r of the date of issue.

Vol . L X X V I I I . N o . 311. PA~T 3.

THE

Q U A R T E RL Y J()UR N A L

OF THE

GEOLOGICAL SOCIETY.

E D I T E D B Y

THE PERMANENT SECRETARY.

SEPTEMBER 23rd, 1922.

t$

[With Ten Plates, illustrating Papers by Dr. H. H. Thomas, Mr. W. G. Shannon, Profi A. C. Seward & Mr. R.E. Holttum,

"~ and Dr. C. W. Andrews.] (

(

( LONDON :

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PARIS :--CHARLES KLINCKBIECK, II RUE DE LILLE.

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(

' Price Seven Sbilbngs and Sixpence.

LIST OF THE OFFICERS AND COUNCIL OF THE

GEOLOGICAL SOCIETY OF LONDON. Elected February 17t;h, 1922.

~t~ilJmt. Prof. A. C. Seward, Sc.D., F.R.S., F.L.S.

Prof. Edmund Johnston Garwood, M.A.,/ George Thurland Prior, M.A., D.So., Sc.D., F.R.S. [ F.R.S.

Richard Dixon Oldham~ F.R.S. Herber~ Henry Thomas, M.A., Sc.D.

Jur~tari~. Walter Campbell Smith, M.C., M.A. I James Archibald ]:)onglas, M.A., B.Sc.

~orti~lz bur~tarm ~:r~a~urtr. SirArchih~ld Geikie, O.M., K.C.B., D.C.L., / Rober t Stamsfield Herries, M,A.

LL.D., Sc.D., F.R.S, J

¢ @ ~NCl [ . . Frederick Noel Ashcroft, ~¢I.A., F.C.S. Francis Arthur Ba~her, M.A., D.Sc., F.R.S. Prof. P e r c y George Hamnall Boswell

O.B.E., D.Sc. Prof. William S. Boulton, D.Sc., Assoc

R.C.Sc. Thomas Crosbee Cantrill, B.Sc. James Archibald Douglas , M.A., B,Sc . . . . John Smith Flett , O.B.E., M.A., LL.D.,

D.Sc., M.B., F.R.S. Prof. Edmund Johnston Garwood, lVI.A.,

Sc.D., F.R.S, Sir Archibald Geikie, O.M., K.C.B., D.C.L.,

LL.D., Sc.D., F.R.S. John Frederick Norman Green, B.A. Frederick Henry Hatch, O.B.E., Ph.D. Robert St~nsfield Herries, M.A.

Prof. Owen Thomas Jones, ]~I.A., D.Se. William Bernard Robinson King, O.B.E.,

M.A. Richard Dixon Oldham, F.R.S. George Thurland Prior, M.A., D.Se.,

F.R.S. Prof. Sidney Hugh Reynolds, M.A., Sc.D. Prof. Albert Charl~m Seward, Sc.D.,

F.R.S., F.L.S. Walter Campbell Smith, M.C., M.A. Sir Aubrey Strahan, K.B.E., Sc.D., LL.D.,

F.R.S. Herbert Henry Thomas, M.A., Sc.D. Prof. William Whitehead Watts , lff.A.,

Sc.D., LL.D., F.R.S. Henry Woods, M.A., F.R.S.

~ t r m a n e n t Dsrretal'!). L. L. :Belinfante, M.Sc.

~£ibrarian. Chrtt. Arthur Greig. M. St. John Hope.

STANDING PUBLICATION COMMITTEE. Prof. A. C. Seward, President.

Mr. W. Campbe]l Smith. Mr. J. A. Douglas. j Secretaries. Mr. R, S. Herrles, Treasurer.

Prof. P. G. H. Boswell. Dr. F. H. Hatch. Sir Aubrey Strahan. Prof. W. S. Boulton. Prof. O. T. Jones. Dr. H. H. Thomas. Dr. J. S. Flett. Mr. R . D . Oldham. Prof. W. W. Watts . Prof. E. J. Garwood. Dr. G. T. Prior. ]fir. H. Woods. ]~Ir. J. F. N. Green. Prof. S. H. Reynolds.

O R D I N A R Y M E E T I N G S OF T H E GEOLOGICAL SOCIETY TO BE H E L D AT BURLINGTON HOUSE.

SESSIO~ ]922-1923. 1922.

Wednesday, November ... . . . . . . . . . . . . . . . . . . . 8*--22 ,, December ... . . . . . . . . . . . . . . . . . . . 6 - -20*

1923. Wednesday, January ... . . . . . . . . . . . . . . . . . . . . . 10"--24"

,, (Anniversary, Friday, Feb. 16th) February ...... 7*--28*

,, ]~arch . . . . . . . . . . . . . . . . . . . . . . . . 1 4 - - 2 8 ~ ,, April . . . . . . . . . . . . . . . . . . . . . . . . . . 18 * ,, May ................................. 2 -- 16 *

June .. . . . . . . . . . . ! ................ 6 ---20 # The asterisks denote the dates on which the Council will mee~.

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T H E G E O L O G Y OF I ~ E W Z E A L A N D . Translated by ]Dr. C. Fe FTSCHER from the works of MM. HOCHSTETTER & PF.TERMANN. Wi01 an Atlas of Six Maps. Price 10s. net. [Pnstage 9d.]

CONTENTS,

PAPERS READ. Page

6. Dr. H. H. Thomas on Xenolithic Tert iary Minor Intrusions in Mull

(Plates VI-X) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

7. Mr. W. G. Shannon on a Composite Sill at Newton Abbot (Plate XI) ...... 261

8. Prof. A. C. Seward & Mr. R. E. Hol t tum on Jurassic Plants from Ceylon

(Plate XII) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271

9. Prof. A. C. Seward on Carboniferous Plants from Peru (Plate XIII) ...... 278

10. Dr. C. W. Andrews on a New Plesiosaur from the Weald Clay of Berwick,

Sussex (Plates XIV & XV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285

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T H E G E O L O G Y O F N E W Z E A L A N D . Translated by Dr. C. E. FISCHER from the works of MM. HOCHSTETTER & PETERMANN. With an Atlas of Six Maps. Price 10s. net. [Postage 9d.]

CONTENTS.

PAPERS READ. Page

11. Dr. F. Dixey on the Norite of Sierra Leone (Plates XYI-XIX) ............... 299

12. Mr. H. B. Milner on the Pliocene Deposits of Cornwall, and their Bcaring ()n the Pliocene Geography of the South-West of.England .................. 348

13. Mr. S. S. Buckman on Certain Jurassic Strata near Eypcsmouth (Dorset) : the Junction-Bed of Watton Cliff and Associated Rocks" . ................. 378

[TITLE-PAGE, CONTENTS, and INDEX 1[,O re1. LXXVIII.]

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