174 



PROFESSOE OWEX ON THE EOSSIL MAMMALS OE AUSTRALIA. 



about three lines in advance of the naso-premaxillary suture, and are bevelled off to an 

 obtuse point from without obliquely inward and forward. Together these bones form 

 the middle third of the upper border of the external bony nostril. The frontals (u) make 

 a slight projection into the middle of the fronto-nasal suture, which from this shallow 

 indent runs outward and a little forward to the nasal process of the maxillary (21) *. The 

 naso-maxillary suture forms the hind fifth part of the lateral border of the nasals ; the 

 naso-premaxillary suture runs along the rest of the extent of the nasal bones ; i. e. to 

 the beginning of their free ends, which are short and subobtuse. 



Nasal bones and their connexions, 

 var. 2, Phascolomys vombatus, Geoffr. 



Nasal bones and tbcir connexions, 

 var. 3, Phascolomys vombatus, Geotfr. 



In a second Tasmanian Wombat the nasals (fig. 1, 15) differ from those above described 

 in their basal breadth, this being equal to rather more than three fourths of their length, 

 or as 77 to 100, also in the absence of any mesial indent of the fronto-nasal suture, and 

 in the sharper convergence forward of the hinder fourth part of the lateral margins. 

 These margins describe a similar wavy course, convex outwards along the middle third, 

 or a little in advance of it. The apices overhanging the nostril are less sharp and pro- 

 minent than in the last or type specimen. 



In a third younger Phascolomys vombatus (fig. 2) the lateral margins converge more 

 gradually and in an almost straiglit line from the base to the anterior fourth of the 

 nasals, where the margins extend nearly straight to the nostril. The middle sixth 

 part of the fronto-nasal suture is slightly concave ; the rest extends outward and more 

 obliquely forward than in the two preceding specimens. Tlie apices of the nasals 

 projecting beyond the premaxillo-nasal sutures arc sharp, and form one fifth the length 



• Thin specimen, fi{?urc(l in ni}- first jjaper {he. cit.), shows the usual characters and is not hero figured: the 

 references to tlie numerical synibols of the bones, in aid of the description, are seen in the subjects of the two 

 VVoodcuto showing the varieties. 



