71 



Miller — Description of a New Rodent. 



Fig. 1."'. — Front foot of Idiu 

 rus vine rot is. (X 1/^-) 



Color above sepia, slightly grayer on posterior half of back, and dark- 

 ening to nearly black on membranes. A faintly indicated dark stripe 

 from base of ear to muzzle. This is perceptible in certain lights only. 

 Throughout the body fur the hairs are dusky plumbeous to within about 



J iniii. of tip. This darker color appears every- 

 where irregularly at the surface. Ventral surface 

 pale yellowish wood brown, irregularly darkened 

 by the plumbeous bases of the hairs. Hairs on 

 under side of membranes very dark brown and 

 with none of the silver gray appearance described 

 in I. zenkeri. Dorsum of manus and pes with short, scattered, dark brown 

 hairs. Fringe on wrist (rig. 15) and side of hind foot dark brown. Tail 

 dark chestnut brown, slightly tinged with yellowish near base. 



Feet. — So far as can be determined from dry specimens, the feet are 

 essentially as in" Idiurus zenkeri. The front foot with its equal digits, rudi- 

 mentary thumb, and fringed wrist is 

 shown in figure 15. 



Tail.— The generic characters of the 

 tail, as described by Mr. Matschie in 

 the type of Idiurus zenkeri, are exactly 

 reproduced in J. macrotis (fig. 16). The 

 pad of projecting scales occupies a space 

 about 17 mm. in length and 4 mm. in 

 width. The proximal end of the pad 

 is about 25 mm. behind the anus. The 

 lateral fringes begin on each side of the 

 proximal end of the scale pad, but the 

 ventral fringe reaches only to a point 

 about 15 mm. behind the pad. The 

 three fringes continue distinct to near 

 the tip of the tail, where the hairs of 

 which they are composed gradually be- 

 come longer and finally blend with the 

 long sparse hairs of the dorsal surface 

 to form the terminal pencil. The hairs 

 of all three fringes are about 4 mm. in 

 length, those of the ventral fringe closely 

 appressed. Long hairs on dorsal sur- 

 face of tail 30-4o mm. in length. 



Ear. — The ears 

 (fig. 17) are much 

 larger than in 1. 



zenkeri and wholly naked both within and with- 

 out, except on the external basal third, which 

 is covered with fur similar to that of the head. 

 With a lens a few very small hairs may be de- 

 tected on the anterior border, but these are in- 

 visible to the unaided eye. In form the ear is 

 very simple and strongly suggestive of that of 



Fig. 



10. — Base of tail I under side i of 

 Idiurus macrotis. (X !%•) 



Fig. 17. — Ear of Idiurus ma 

 crotis. (X iy a .) 



