SIXOPA ETHIOPICA. 23 



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blade and a small talon. The high anterior portion consists of an antero-internal and 

 a postero-external cusp, which tend to form a cutting-blade, and a small postero-internal 

 cusp. The talon in the typical species is more or less basin-shaped. 



It is with considerable hesitation that the fragment of a mandible described below 

 has been referred to a member of this genus, which has hitherto been almost, if not 

 quite, confined to North America. The European genera Cynohycenodon and Proviverra 

 are very closely allied to Sinopa, but the present specimen differs from the mandibles of 

 species referred to them both in being considerably larger and in possessing more 

 massive molars, the cusps of which are neither so high nor so pointed. Eiitimeyer * 

 has already referred a small Creodont from the Eocene of Egerkingen to Stypolophus^ 

 (Sinopa), distinguishing it from Froviverra and Cynohycenodon on these same grounds, 

 and his specimen must be very similar to that now described and made the type of a 

 new species. 



Sinopa ethiopica, sp. nov. 



[Plate XIX. figs. 6, 6 a.] 



Type Specimen. — Portion of left ramus of mandible with pm. 4 and m. 1-3 in situ 

 (PI. XIX. figs. 6, 6 a) ; Geological Museum, Cairo. 



This species is about the same size as Sinopa agilis (Marsh), but differs from it, 

 and apparently from the other American species also, in the relatively smaller size of 

 the last premolar and first molar compared with the last molar. It also differs from the 

 typical members of the genus in having a trenchant talon, the cutting-edge of which 

 is situated rather towards the outer side of the tooth ; in the other species the talon is 

 basin-shaped. This difference suggests that when more is known of its structure, this 

 species may require to be placed in a new genus. 



Form. & Log. — Fluvio-marine beds (Upper Eocene) : north of Birket-el-Qurun. 



C. 10193. Portion o£ the left ramus of the mandible with the somewhat broken molars and fourth 

 premolar. Type specimen figured on PI. XIX. figs. 6, 6 a. 



The ramus, so far as preserved, is of nearly the same depth throughoiit ; posteriorly 

 it is broken away about 1-5 cm. behind the last molar ; there seems to have been a well- 

 marhed masseteric fossa. The last premolar (^pm. 4) consists of a large, somewhat 

 compressed, main cone, with small anterior and posterior basal cusps, the posterior one 

 being the smaller and forming a short cutting-talon ; the basal length of this tooth is u. 

 little greater than that of m. 1. The molars increase in size from before backwards. 

 Each consists of a high tricuspid anterior portion and a talon. In all the teeth the end.s 

 of the main cusps have been broken away, but it can be seen that the postero-external 

 cusp was the largest and with the antero-internal formed an imperfect cutting-blade ; 

 the postero-internal cusp is small and intimately connected with the inner face of the 



* Abhandl. Schweiz. Pal. Ges. vol. sviii. (1891) p. 104, pi. vii. figs. 10, 11. 



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