CHARACTERS OF THE LEMURS AND TARSIUS. 



21 



■of the rliinavinm ; but in the length and shape of the rhinarium 

 G. seveqalensis is intermediate between G. crassicaiidatus and 

 //. demicloffi (text-figs. 1, G; 2, B). 



In Ghiromys the i-hinarinm is not so prominent ; the nostrils 

 are longer, more slit-like, and separated in front by a narrower 

 septmn. The infivanarial portion is very deep towards the middle 

 line, reaching almost to the edge of the upper lip and making the 

 labial extension of the rhinarium appear very short. In this 

 genus also the frenum which ties the lip to the gum between the 



Text figure 1. 





A. Rliinarium of Chirogalous major. 



B. Rhinarium of G-alac/o crassicaiidatus . 



C. Rhinarium of HemigaJago demidoffi. 



D. Bhinarium of Chiromtjs. 



E. Nose of Tarsius. 



points of insertion of the incisor teeth is somewhat longer than in 

 "typical Lemurs, so tha,t the lip is capable of being protruded to a 

 slightly greater extent in the middle line. It is probable that 

 the variations of the rhinarium and upper lip, like many of the 

 structural characters in Ghiromys, are correlated with the rodent 

 dentition and peculiar method of feeding of this Lemur ; but our 

 knowledge of the function of the rhinarium is too imperfect to 

 warrant more than a suggestion on this point (text-fig. 1, D). 



