BY R. BKOOM. 565 



which passes somewhat downwards. The large depression on the 

 outer side is bounded in front by a well marked ridge, but does 

 not communicate with the dental canal. The main portion of the 

 jaw supporting the molars and the large premolar is very stout 

 proportionately. In the upper jaw only the cheek teeth are at 

 present known. There is a large premolar grooved and serrated 

 as in the lower jaw, having six well marked grooves which run 

 downwards and backwards. The grooves run parallel to the 

 anterior border and leave the posterior and upper third of the 

 tooth ungrooved. Behind the large premolar are three true 

 molars : whether there may be a rudimentary fourth as in the 

 lower jaw is at present unknown. The first is the largest. It 

 has two moderately large blunt tubercles on the outer side, and 

 two smaller ones on the inner, while a small fifth is situated at 

 the anterior and inner corner. The upper third molar is small. 



The following are some of the principal measurements :— 



From 1st to 3rd upper molars 3-2 mm. 



Length of 1st upper molar 1-3 mm. 



Height of upper premolar 1-7 mm. 



Length (antero-posterior) of ujDper premolar ... 2-0 mm. 



From 1 st to 3rd lower molars 3-5 mm. 



Length of lower incisor 6*3 mm. 



From point of lower incisor to front of premolar 8*2 mm. 



Depth of lower jaw at 1st molar 3-5 mm. 



Locality. — Near Taralga, N.S.W. 



Geological Formation. — Pleistocene (?). 



Of this form I have discovered fi,ve or six moderately good 

 lower jaws, the anterior portion of another, and three fragments 

 of the upper. The hard matrix and the friable nature of the 

 bones render it very difficult to develop the more delicate 

 specimens, and in the case of Burramys the difficulty is enhanced 

 by the obliquity of the large premolar, so that it becomes almost 



