THE TEETH OF MARSUPIALIA. 



429 



The Kangaroos, comprising many species of very varying 

 size, are all docile creatures (with the exception of a few old 

 males), of herbivorous habits; they in some particulars 

 recall the ruminants. 



Their dental formula is 



. 3 



i _ c ~ 

 1 



1 4 

 p . m -. 



The three pairs of upper incisors are more equal in size 



ji nv 



than in the Hypsiprymnus, and the central pair do not 

 ;grow from persistent pulps. The lower incisors are very 

 peculiar teeth : they grow from persistent pulps, are pro- 

 cumbent, projecting forwards almost horizontally, and are 

 very much flattened from side to side, their outer surfaces 

 being but slightly convex, and their inner surfaces flat, with 

 a median ridge. Their margins are almost sharp. There is 

 an unusual amount of mobility between the two halves of the 



0) Upper and lower teeth of Halmaturus ualabatus. The permanent 

 premolar is not yet erupted, and is shown in its crypt : when it comes 

 into its place it will displace the milk molar, and one of the anterior pre- 

 molars as well. In the upper jaAv a rudimentary canine is shown. The 

 point of the lower incisor would fit, in closure of the mouth, behind the 

 long anterior upper incisor, but the width of the page did not admit of the 

 teeth being placed in their true relative positions without reduction in 

 size. 



