60THE LARGEST TOOTH OF THE WOLF EXCAVATED

IN JAPAN

By Hirokichi Saito

The largest tooth of the wolf the world had ever known was excavated in the

fall, 1953 from the lime stone mining place near Shiriya-zaki on the north-eastern

extremity of Shimokita Peninsula, the right side of the northern extremity of the

Japan Mainland.The tooth was discovered from the lime stone cave after blasted with gun-

powder by Nittetsu Kogyo Company with the purpose of excavating lime stone, and was found to be the lower left first molar of the wolf. It is owned by Mr.

Zenji Nakajirna of Tanabu High School, Aomori prefecture, and is now kept by

Mr. Naora, professor of Waseda University.

Fig. 1. Lower Left Molar

(in natura size)

The root of the molar is broken up, but for-

tunately, the crown is perfect with posterior part

of Cingulumspitze a little missing. The geological

age of the fossil is pleistocene and it is entirely

fossilized and the crown wears a beautiful white

lustre.

The length from anterior to posterior of the

crown of the molar is 34.5 mm, the breadth of the

anterior part of the crown is 13.5mm, the breadth

of the posterior part of the crown is 11.5 mm and

the height of the crown at the protoconid on the

outer side is 22 mm.

The lower right first molar of another wolf

has been discovered from the same place where

the above molar was excavated, but it is 27.5mm

in length and of the same size as that of a modern

wolf.

In Japan the three fossils of the lower first

molar belonging to the same geological age have

been found out of the lime stone cave in Kuzuwu,

about middle part of the Mainland, and they are 30mm, 29.5mm and 29mm in

Jour. Maui ii. Soc. Japan, vol. 1, no. 4 June 1957.

1957年6月 Largest Tooth of Wolf 61

length respectively and as large as that of a common wolf (Canis 1. 1.).

Fossils of the wolf in China belonging to the same geological age have been

found at Choukoutien (near Pei-Ping) where that famous Sinanthropus was found

and the length of the largest one is only 26.3 mm.

After the Japan Stone-age nine subfossils of the lower first molar have been

found the largest of which was found in Shikoku Island and is 28.2 mm in length,,

and even the largest one among the same teeth of the twenty three Japanese wol

ves (Canis 1. japonicus) _is 28.5 mm. Even the largest one among the teeth of

the six Hokkaido wolves (Canis 1. 1.) belonging to the same lineage as that of the:

Siberian wolf is 31 mm (Canis 1. rex type).

And the largest one among the teeth of eleven Korean wolves (Canis 1. kore

anus) is 27.5 mm, and the largest of the teeth of the three Manchurian wolves

(Canis 1. laniger) is 29 mm.Among the specimens of sixty-nine wolves owned by the British Museum, only

three are over 30 mm•`31 mm, 32.5 mm and 33 mm respectively. The wolf with

the tooth 32.5 mm tooth is an adult male (Canis 1. occidentalis) seized in Fort

Simpson of North America, and it has been said to be the largest one of all the

teeth of the wolf.

This lower left first molar of fossils of the wolf discovered at Shiriya-zaki is

larger than that of the wolf seized in Fort Simpson and it is considered to be the

largest one among the fossils, subfossils and modern specimens which have ever

been found in the world.

Measurements of the Lower Carnassial Teeth of Wolves (in mm)

Age Synopses Length of Measuredthe tooth by

The Geological The newly excavated specimen 34.5 mm H. Saito

Age

•V The largest of the four M. T. 30.0 mm

•V except the newly excavated

•V The larger of the two M. T. 26.3 mm Pei Wen-Chung

found in China

The New Stone The largest of the nine M. T. 28.2 mm H. Saito

Age found in Japan

The Present Age The largest of the 26 Canis l . 28.5 mm •V

japonicas

•V The largest of the six Canis l. l., 31.0 mm •V

Hokkaido

•V The largest of the 3 Canis l. 29.0 mm •V

laniger, Manchuria

62 哺 乳 動 物 学 雑 誌 vol. 1, no. 4

The Present Age The largest of the 3 American 31.0 mm A. Wolfgramm

wolves

•V The largest of the six European 30.0 mm •V

wolves

•V The largest of the 69 specimens 33.5 mm R. I. Pocock

owned by the British Museum

Literature

A. Walfgramm : Die Eintwerkung d. gefangenschaft auf d. Gestaltung d. Wolfs-

schadels. Zool. Jahrb., Abt. f. Syst., usw., VII Bd. 1894.

Pei Wen-Chung : On the Carnivora from Locality I of Choukutien. Pal. Sin., Ser.

C. Vol. VIII, Fas. 1. 1934.

R. I. Pocock : The Races of Canis lupus. P. Z. S. London 1935.

H. Saito : On the Japanese Wolves Skeleton in the Tokyo National Science Mu-

seum. The Museum Studies, Vol. XI, No. 4. 1938.

H. Saito : On Canidae Fossils from Ku-Hsiang-tung, Manchuria, and from Japan.

Report of the First Scientific Expedition to Manchoukuo. Sec. II, Part IV.

1939.

Jour. Mamm. Soc. Japan., vol. 1, no. 4, June 1957.