SIRENTA. 



The following specimens are not specifically determined. 

 40859. Fragment of a left maxilla, showing the last two molars; from 

 (Fig.} the Middle or Lower Miocene of Gozo, near Malta. This 

 specimen is described and figured by Leith-Adams in the 

 Quart. Journ. Geol. Soc. vol. xxxv. p. 526, pi. xxv. figs. 3, 

 3 a, and provisionally referred to H. schinzi. The teeth 

 (which are of small size) do not, however, agree with 

 those of any examples of that species in the Museum. 



Presented by Admiral Spratt, C.B., 1867. 



M. 1938. An unworn last left lower molar, with a large third lobe ; 

 locality unknown. 



Presented by Prof. Sir R. Owen, K.C.B., 1884. 



M. 2410. Two unworn lower molars ; locality unknown. 



Purchased, 1885. 

 35578. Fragment of a rib ; from the Miocene of Malta. 



Presented by Sir W. Reid, 1860. 



Halitherium (?) sp. 

 Hob. N. America. 



41846 a. The centrum of a lumbar vertebra, and portions of two 

 ribs ; from the Phosphate beds (Eocene) of the Ashley 

 river, South Carolina, U.S.A. These specimens were 

 associated with Zeuylodon. 



Presented by Cowlan Gravely, Esq., 1869. 



Genus PRORASTOMUS, Owen \ 



Dentition : I. *, C. {, Pm. and M. | 2 (?). This genus appears to be 

 a generalized form allied to Halitherium, but having a fuller dentition 

 and lacking the distinct deflection of the premaxillte and the man- 

 dibular symphysis. The true molars are of a Dinotherioid type, 

 and the upper incisors are not tusk-like. 



Prorastonms sirenoides, Owen 3 . 



This is the type and only known species, and is of smaller size 

 than Halitherium schinzi. 

 Hob. West Indies. 



1 Quart. Journ. Geol. Soc. vol. xi. p. 541 (1855). 



2 This is the number given by Owen, but it is doubtful if it is correct. 



3 Loc. cit. 



