32 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



TOL. 45. 



Dental characters.— The teeth of Tupaia are the most generalized of 

 any genus in the family. The two pairs of upper incisors are usually 

 subequal, although the first is nearly always a little the larger. In 

 certain species T. nicoharica, T. javavica, T. minor, T. gracilis, how- 

 ever, there is a marked difference in size, but it is always the first pair 

 which is the larger of the two. This difference in size is fairly useful 

 as a group character, but can not be relied upon as a hard and fast 

 one, as specimens showing intermediate degrees of development are 

 found. There are three pairs of lower incisors, all well developed 



ftf>. 



<.d«. 



hy,ihn: 



i.dP. 



i.d* 



- i.dP. prx.e 



— then. 



prx.vn. 



Fig. 3.— Palmar surface of eight forefoot and plantar subface of 

 eight hindfoot of tup^ua glis ferruginea. cat. no. 124319, u. s. n. m., 

 Singapore. Enlarged about t-wice. After Gregory, Bulletln Ameri- 

 can Museum of Natural History, vol. 27, 1910, p. 270. Hy. thn, hypo- 

 thenar pad; i. d', i. d^, i.d^, i. d*, first, second, third and fourth 

 interdigital pads; prx. c, proximal external pad; prx. in, proximal 



INTERNAL PAD; thCTl, THENAR PAD. 



and functional, but the third pair is much smaller than the others; 

 the second pair is somewhat larger than the first pair. In some cases 

 the third pair is relativel}^ more reduced in size than in others, and in 

 these cases the tooth is barely functional. This is particularly so in 

 those species which have the greatest development of the central upper 

 incisors and is also correlated with a greater development of the lower 

 canine. In this connection it is interesting to note that in the genus 

 Urogale where the third lower incisors are quite rudimentary we find 

 a very unusual development of the lower canine, and of the second 



