44 UNGULATA. 



19952 C. Part of the left ramus of the mandible of a young indi- 

 (Fig.) vidual, containing mm. 4 and m~T, the latter unworn ; from 

 Buenos Ayres. This specimen is figured by Falconer and 

 Cautley, op. cit. pi. xl. fig. 13, and also in ' Falconer's 

 Palseontological Memoirs,' vol. i. pi. viii. fig. 1 l , as M. 

 andium. The double trefoils are shown in the second 

 ridge of mm. 4 ; there is a cylindrical incisive alveolus. 



Purchased. Before 1840. 



39374. The germ of the second right lower true molar ; from the 

 Kio Negro. The hind talon is of moderate size. 



Presented by D. A. Stoddart, Esq., 1865. 



43254. The second left lower true molar, in a well-worn condition -, 

 from Buenos Ayres. 



Presented by Senor L. J. Fontana, 1871. 



19952 d. The second left lower true molar, in a more worn con- 

 dition ; from Buenos Ayres. The second aud third ridges 

 are more worn than the first. Purchased, 1846. 



44135. The third right lower true molar, in a partially worn con- 

 dition ; probably from the Bio Negro, Purchased, 1873. 



19952 e. The third right lower true molar, in a partially worn con- 

 (Fig.) dition; from Buenos Ayres. Figured by Falconer and 

 Cautley, op. cit. pi. xl. fig. 11, under the name of M. an- 

 dium. There are four ridges and a double hind talon. 



Purchased, 1846. 



19952 f. Fragment of the left ramus of the mandible, containing 

 the partially-worn m73 (imperfect anteriorly) • from 

 Buenos Ayres. The hind talon is very large. 



Purchased, 1846. 



M. 2952. Fragment of the left ramus of the mandible, containing 

 m7~3, of which the talon is wanting ; from South America. 



No history. 



M. 2953. Fragment of the right ramus of the mandible, with m7d, 

 of which the talon is wanting ; from South America. 



No history. 



1 In the description of the plate the teeth are named the second and third 

 milk-molars ( = mm. 3 and mrn.1); but there seems no reason for this view, 

 which introduces an abnormal ridge-formula. 



