SL 
there is a tendency for a suppression of the milk dentition and a re- 
appearance of the 4th set of teeth. 
Diprotodonta. 
Much less is known concerning the precence of a premilk den- 
tition in the diprotodont Marsupials but it is nevertheless present in 
several genera and probably when young enough specimens are examined 
it will be found in more. 
Macropodidae. 
As already mentioned I am now disposed to regard the three 
minute teeth which I described (12) in the upper jaw of several genera 
belonging to this family as the premilk predecessors of the 3 functional 
incisors. With regard to those in the lower jaw, while the probably 
belong to the premilk set I do not think either of them can be con- 
sidered as the premilks to the functional incisor for the anterior one 
(l. ec. fig. 9 and 10) exhibits the enamel germ of a successor, while 
the posterior one was situated too far back in the jaw. 
Trichosurus vulpina. 
In this genus the only conspicuously developed trace of the pre- 
milk dentition was seen in connection with 23, this labial outgrouwth 
had in one case all the structure of a small bell-shaped enamel organ, 
in addition labial outgrowths were seen in connection with ii and i2 
and pm 1, 
Phalanger (Cuscus). 
In a younger specimen of this closely related form several calci- 
fied premilk teeth were present, that connected with ©1 alone being 
uncalcified 
Premilk teeth, 7. =" 
In the lower jaw a trace of a vanishing tooth was seen it being 
either an incisor or the canine. 
Acrobates. 
The specimen was too old to show any trace of the premilk teeth, 
but as with all the older animals, the lingual developments of the 
dental lamina were conspicuous. 
dpm 4 was small and highly calcified, but in the lower jaw there 
was only one tooth to be seen representing pm 4, but whether dpm 4 
Or ppm 4 was uncertain. 
