MILK DUCTS 



51 



number fifteen, which is said to occur in 

 several sjaecies of kangaroo, is— so far as we 

 know — only surpassed in the genus Phas- 





I 





vrf; 



'% 



.,''***^„ 





Fig. 17.— "Pkkamys henseli," showing Arrangement 

 OF Nipples. (After Thomas.) 



colarctos, in which twenty-four ducts are to be 

 found. Histologically the milk glands of the 

 Marsupialia are very much like those of the 



