318 



shares to the wedge, which is longer (as shown by the lower dotted lines, «, <z, in fig. 4). 

 Outside this, in all Latifront Wombats, the fronto-nasal suture runs straight outward to 



Fig. 4. 



IS' 



Nasal bones and their connexions-, Phascolomys latifrons, Ow. 



the lacrymal (73), from which bone it is not separated, as in Phascolomys platyrhinus and 

 Phase, vombatus, by the maxillary (21). The extent of the naso-maxillary suture (15-21) 

 equals that of the naso-premaxillary suture (15-22). 



These differences in the connexions of the nasals are more significant of specific 

 distinction than the shape of the bones. The naso-maxillo-premaxillary suture (15-21-22) 

 is very slightly concave outwardly in the Latifront Wombat ; and the free border of the 

 nasals beyond the suture affects a convex bend toward the apices. 



§ 5. Nasal bones in Phascolomys Mitchelli, Ow. — There would be no doubt in deter- 

 mining Phascolomys latifrons by the naso-maxillo-premaxillary part of the skull, at least 

 as being distinct from the other two known recent species, if even the still more charac- 

 teristic part of the frontal bones was wanting. There might be more difficulty in pro- 

 nouncing as to whether a fore part of the skull belonged to Phascolomys platyrhinus or 

 to Phase, vombatus. 



I now proceed to compare such a fragment of a fossil skull of a Wombat on the basis 

 of the characters which comparisons of different individuals of the three well-determined 

 recent species of Phascolomys affords. 



The fragment in question (Plate L. figs. 1, 3, 4, 5) includes the nasals (is) with 

 parts of the frontals (n), lacrymals (73), malars (26), maxillaries (21), premaxillaries (22), 

 and palatines (20). The nasals (15) are of the type of those in Phascolomys vombatus and 

 Phascolomys platyrhinus; in the proportion of basal breadth to length and the speedy 

 narrowing as they advance they resemble the modification shown in Woodcut, fig. 1, 

 p. 316, in Phase, vombatus. But small as is the extent of the naso-maxillary suture 



