EQTJID.3!. 65 



and it presents distinctive characters in the upper premolars ; the 

 plication of the enamel is comparatively slight, and the cement very 

 thick externally. The foot 1 is stout and has three digits. 

 Hob. India and (?) China. 



M. 2665. The second left lower premolar ; from the Pliocene 

 Siwaliks near Peshawar, Punjab, India. 



Presented by Sir R. I. Murehison, Bart. 



28585. A left upper cheek-tooth, provisionally referred to this 

 species; from the Pliocene (?) of the south of China. 

 This specimen agrees in size with the true molars of the 

 specimen figured by the present writer in the ' Palseon- 

 tologia Indica ' (Mem. Geol. Surv. Ind.), ser. 10, vol. ii. 

 pi. xi. fig. 3. Presented by D. Hanbury, Esq., 1853. 



37391. A left astragalus, perhaps belonging to this species ; from 

 the Siwaliks of Perim Island, Gulf of Cambay. 



Presented by A. Rogers, Esq., 1863. 



Genus EQUUS, Linn. 2 

 Including Hippidion, Owen 3 . 



Dentition: I. |, C. |, Pm. ^, M. |. In existing species the 

 first upper cheek-tooth is usually absent in the adult, but is re- 

 tained in some extinct species ; rarely the first tooth of the typical 

 series is present in the lower jaw of young animals, as in one young 

 example of E. sivalensis (No. 22108), and in another of E. hemi- 

 onus *. The anterior " pillar " in the upper cheek-teeth is con- 

 nected with the anterior inner " crescent " throughout its length, 

 and there is but one digit to each foot. The so-called Hippidion 

 is distinguished by the upper cheek-teeth having short and much- 

 curved crowns, in which the anterior and posterior pillars are of 

 equal size, and by the existence of a rudiment of the fifth meta- 

 carpal. These characters the writer is not disposed to consider of 

 generic value ; the great curvature of the crowns of the upper 

 cheek-teeth is a character recalling Toxodon and Nesodon, andis 

 unlike Hipparion. A maxillary fossa may be present (E. andium 

 and E. sivalensis). 



1 ' Palseontologia Indica ' (Mem. Geol. Surv. Ind.), ser. 10, yol. ii. pi. xii. 



2 Syst. Nat. ed. 12, vol. i. p. 100 (1766). 



3 Phil. Trans, for 1869, p. 572 (1870). As a subgenus. 



4 See Flower, Cat. Vert. Anim. Mus. R. Coll. Surg., pt. ii. Mammalia, p. 413, 

 no. 2108 (1884). 



PART III. F 



