ANTHKACOTHEKIID^!. 219 



Ancodus incertus, Pomel 1 . 

 Sothriodon platyrhynchus, Aymard 2 . 

 Hyopotamus borbonicus, P. Gervais 3 . 

 Hyopotamus vectianus, Owen 4 (in parte). 



The mandibles of the smaller hypsodont Hyopotamus from the 

 Hempstead beds of the Isle of Wight are indistinguishable from those 

 of the typical llonzon H. velaunus, and are accordingly referred to 

 the same species '. It has not, however, been found possible to 

 separate the upper teeth of the smaller Isle-of-Wight species from 

 those of H. bovinus (q. v.), as an associated series has not been found. 

 The present species is a hypsodont form, distinguished from H. bo- 

 vinus by its smaller teeth and well-marked cranial differences. 



Hab. Europe. 



M. 1946. Cast of the cranium. The original is from the Lower 

 Miocene of Ronzon, near Puy-en-Velay (Haute-Loire), 

 France ; it is figured by Kowalevsky in the Phil. Trans, 

 for 1873, pi. xl. figs. 1, 2, and is apparently the same as 

 the one figured by Filhol in the Ann. Sci. Geol. vol. xii. 

 pis. xvii., xviii. Presented by Dr. Kowalevsky. 



M. 1947. Cast of the left ramus of the mandible of a young individual, 

 showing the milk-dentition. The original is from the 

 Lower Miocene of Ronzon; and is figured by Kowalevsky, 

 op. cit. figs. 3, 4 (the latter enlarged), and also by Filhol, 

 op. cit. pi. xxii. fig. 102. The teeth are considerably 

 smaller than those of the immature mandible of H. bovinus, 

 No. 29802, on which account the specimen is referred 

 to the present smaller species. 



Presented by Dr. Koivalevsky. 



M. 1948. The left ramus of the mandible of a young individual, with 

 the milk-dentition ; from the Lower Miocene of Ronzon. 

 Presented by Dr. Kowalevslcy. 



M. 2181. Fragment of the right ramus of the mandible of an imma- 

 ture individual, showing mm. 3, mm. 4, and a part of m . 1 ; 

 from the Lower Miocene of Ronzon. This specimen agrees 

 with the two preceding ones, the length of mm. 4 being 

 0,0205. Purchased, 1885. 



1 Catalogue Methodique, p. 92 (1853). 



2 Ann. Soc. Agric. Sci. le Puy, vol. xii. 1848 (teste Filhol). 



3 Zool. et Pal. Francises, ed. 1, vol. ii. Exp. No. 23, p. 1 (1848-52). 



4 Quart. Journ. Geol. Soc. vol. iv. p. 103 (1848). 



8 Vide Lydekker, Geol. Mag. dec. 3, vol. i. p. 547 (1884). 



