﻿276 Allen's naturalist's library. 



GENUS PHASCOLOTHERIUM. 



Phascolotherium^ Owen, Trans. Geol. Soc, ser. 2, vol. i., pt. i, 

 p. 58 (1841) ; Lydekker, Cat. Foss. Mamm., pt. v., p. 

 270 (1887). 



This genus, as represented by P. hucklandi of the lower 

 Jurassic rocks of Stonesfield, near Oxford, was one of the 

 earliest discovered of the Secondary Marsupials, and is charac- 

 terised by having only seven pairs of cheek-teeth (including 

 premolars and molars). The molars had three cusps arranged 

 in a longitudinal line, of which the middle one was much 

 larger than the others, while there were minute accessory cusps 

 at the two extremities of each tooth, and a distinct ledge at 

 the base of the inner side. The whole length of the lower 

 jaw was only about an inch. 



GENUS AMPHILESTES. 



Amphilestes, Owen, Encyclopaedia Britannica, 8th ed., vol. 

 xvii., p. 157 (1859); Lydekker, Cat. Foss. Mamm. Brit. 

 Mus., pt. v., p. 271 (1887). 



In this genus, as represented by A. broderipi, of the Stones- 

 field rocks, the molar teeth were of the same general structure 

 as in Phascolotherium, but much more numerous, the total 

 immber of teeth being probably the same as in the next genus. 

 The one species was exceedingly minute. 



GENUS AMBLOTHERIUM. 



Amblotherium, Owen, Mesozoic Mam.m., p. 29 (1871); Lydek- 

 ker, Cat. Foss. Mamm. Brit. Mus., pt. v., p. 274 (1887). 



A second group of the family is represented by the minute 

 Aniblothenuin soricinimi, of the upper Jurassic Purbeck xock^. 



J 



