MB. R. LYDEKKER ON A JAW OE HYOTHERIUM. 



19 



3. Description of a Jaw of Hyotherittm, from the Pliocene of 

 India. By E. Lydekker, Esq., B.A., E.G.S., &c. (Head No- 

 vember 3, 1886.) 



I am again indebted to Col. J. W. Watson, the Political Resident 

 in Kattiawar, for an interesting addition to our knowledge of the 

 Siwalik fauna of Perim Island, on the western coast of India. The 

 specimen in question (which Col. Watson has presented to the British 

 Museum) is a portion of the left maxilla, with the three true molars, 

 of a species of Hyotherium, which is apparently distinct from any 

 named form. The fragment, of which an oral view is given in the 

 accompanying woodcut, has been slightly water-worn, but not to 

 such an extent as to damage it materially ; the first molar has the 

 dentine of the summits of the columns exposed by attrition, while 

 the third molar is scarcely affected by such action. The teeth carry 



Hyotherium perimense. Part of the left maxilla ; from the 

 Siwalilcs of Perim Island. (Nat. size.) f British Museum. 

 No. M. 3501.) 



m. 1. in. 2. m. 3. 



the usual four main columns, with accessory columns on the inner 

 side of the median longitudinal cleft, and have a well-marked and 

 crenulated cingulum on the inner and fore-and-aft surfaces. The 

 crowns of the first aud second molars are squared and rather- broader 

 than long,, while that of the third tooth has its postero-internal 

 angle produced and its outer border sloping towards the median line. 



The specimen may without doubt be referred to the genus 

 Hyotherium, in the sense in which (following the lead of the late 

 Prof. Peters) I have employed that term in the 6 Catalogue of the 

 Fossil Mammalia in the British Museum ' *, and we may accordingly 

 proceed to compare it with the named European t and Asiatic 



* Part ii. pp. 253-258 (1885). 



t A partial synonymy of tbe more important European species is given in 

 the work cited. It has been subsequently stated by Dr. Max Schlosser that 

 Choeropotamits stein heimensis, Fraas, is the same as H. Scemmeringi. 



c 2 



