XIPHODON 337 



incisors, which now forms part of the palseontological collec- 

 tion in the British Museum. The dental formula, as shown 

 by the mandibular teeth, and by the evidence on their crowns 

 of the presence of the teeth of the upper jaw, is the typical one 

 in diphyodont Mammalia, viz. — i |5f , c ^j P jE^ m |zf = 44. 

 The canine, with a crown like that of the first premolar, and 

 not longer, is separated from it by an interval of half the 

 breadth of the crown, and by a narrower interval from the 

 outer incisor. The first premolar is divided by an interval of 

 scarce a line's breadth from the second. The rest of the molar 

 series are in contact. The total length of the lower jaw is 

 5 inches 11 lines (0 m- 148) ; that of the molar series is 2 inches 

 11 lines (0 m, 075) ; that of the three true molars is 1 inch 4i 

 lines (0 m- 035). The near equality in height of the crowns of 

 all the teeth, and their general character, show that the animal 

 belonged to the anoplotherioid family. The dentition of the 

 present species differs from that of Dichodon in the absence 

 of the accessory cusps on the inner side of the base of the true 

 molars ; and both from Dichodon cuspidatus and Xiphodon 

 gracilis in the minor antero-posterior extent of the premolars ; 

 it corresponds with Dichobune (as represented by the D. 

 leporina, Cuvier) in the proportions of the premolars and in 

 the separation of the canine from the adjoining teeth : to 

 this genus, therefore, the fossil is referable, provisionally, 

 in the absence of knowledge of the molars of the upper 

 jaw, which are the most characteristic : and the writer has 

 proposed to call the species, from the size of the animal repre- 

 sented by the fossil, Dichobune ovina. It is from Hampshire 

 eocene. 



Genus Xiphodon. — The genus Xiphodon was indicated, and 

 its name proposed, by Cuvier, for a small and delicate, long 

 and slender-limbed, anoplotherian animal, which, in his first 

 Memoir {Annates du Museum, torn, iii., p. 55, 1803), he had 

 called Anoplotherium medium; but he altered the name, in 



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