228 UNGULATA. 



29776. The fourth left lower premolar ; from the Hempstead beds 

 of the Isle of Wight. 



Hastings Collection. Purchased, 1855. 



29906. Numerous incisors belonging to this or the preceding spe- 

 (Fig.) cies ; from the Hempstead beds of the Isle of Wight. 



Some of these specimens are figured by Owen, op. cit. 



pi. vii. figs. 10, 12, 13, 15, 15, 23. 



Hastings Collection. Purchased, 1855. 



Hyopotamus americanus, Leidy '. 



This is a hypsodont form, with upper molars very like those of 

 the last species. 

 Hab. N. America. 



47502. Cast of a fragment of the right maxilla, containing m. 2 and 

 m. 3, the latter unworn. The original is from the " Mau- 

 vaises Terres " of Dakota ; and is figured in Journ. Ac. 

 Nat. Sci. Phil ad. ser. 2, vol. vii. pi. xxi. fig. 1. 



Presented by Prof. J. Leidy, 1876. 



Hyopotamus porcinus, P. Gervais 2 . 



This species is somewliat smaller than AntJtracotherium minus, 

 and its upper molar teeth are of a brachydont type, and, as observed 

 by Gervais, intermediate in structure between those of the typical 

 A. magnum and the typical hypsodont Hyopotamus velaumis. 

 The lower molars provisionally referred to this species present no 

 distinctive differences from those of Anthracotherium ; and this 

 species therefore affords additional evidence of the real unity of 

 Hyopotamus and Anthracotlierium. 



Hab. Europe. 



29842. Fragment of the left maxilla, containing the first and second 

 (Fig.} upper true molars ; from the Hempstead beds (Lower 

 Miocene) of the Isle of Wight. The teeth of this specimen 

 (which are figured in the accompanying woodcut, fig. 31) 

 agree so exactly with the two type teeth figured by P. 

 Gervais (loc. cit. 2nd ed. pi. xxxi. fig. 8) that there is 

 every probability of the specific identity of the two ; and, 

 in the absence of any evidence to the contrary, they may 

 be associated. The dimensions of m. 1 are 0,014 x 0,015, 



1 Proc. Ac. Nat. Sci. I'liilnd. v>l. viii. p. 59 (1856 ; vol. dated 1857). 



2 Zool. et Pal. Francises, 1st ed. vol. ii. Exp. No. 31, p. 1 (1848-52). 



