270 



MARStTPIALIA. 



Genus PHASCOLOTHERIUM, Owen \ 



Dentition: I. -, C. \, Pm.+M. ^. Molars and prcmolars very 

 similar in structure; a diastema between lower canine and pre- 

 molars ; true molars tricuspidate, with inner cingulum, which has no 

 cusp on the inner side of the crown, but develops a distinct accessory 

 cusp at each extremity of the crown ; mandibular ramus deep. 



Owen considered that there were probably only three lower 

 incisors, but the writer is convinced, from an examination of the type 

 specimen, that there were four of these teeth. 



Phascolotherium bucklandi (Broderip 2 ). 

 Syn. Didelphis bucklandi, Broderip 3 . 



Thylacoiherium bucklandi, Valenciennes 4 . 



This is the type and only named species ; and was about equal in 

 size to Phascogale penicillata ; the length of the lower series of 

 cheek-teeth being 0,012. 



Hob. Europe (England). 



112. The nearly entire right ramus of the mandible, containing 

 (Fig.) all the teeth except 174 ; from the Lower Jurassic Slate of 



Fig. 40 



Phascolotherium bucklandi. Inner view of the right ramus of the mandible ; 

 from the Stonesfield Slate, f. The outline figure is nat. size. (From 

 Owen's ' Palaeontology.') 



Stonesfield, Oxfordshire. This specimen (woodcut, fig. 40) 

 is the type, and is figured by Broderip in the ' Zool. Journ.' 

 vol. iii. pi. xl. ; by Buckland in his ' Bridgewater Treatise,' 



1 Trans. Geol. Soc. ser. 2, vol. vi. pt. 1, p. 58 (1841). 



a Zool. Journ. vol. iii. p. 411 (1828). Didelphis. * Loc. erf. 



* Oomptes Rendus, vol. vii. p. 580 (1838). 



