528 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



paid to cranial characters seems to have been confined to the number 

 of upper incisors. Before proceeding- to a description of the species 

 in the genus, it will be well to consider some characters of the Slow 

 Lemurs as a whole. 



PELAGE AND COLOR. 



Two different types of hairs are found on the Slow Lemurs: (1) A 

 ver}" dense wooll\" crinkly coat, corresponding in general to what is 

 known as the underfur in mammals, about 20 nmi. in length, on mid- 

 dle of back; and (2), a set of longer hairs, much more scant than the 

 dense woolly ones and from 5 to 10 mm. longer, being nearl}' straight 

 throughout their length, slight crinkling taking place for a distance of 

 5 to 10 mm. along the middle. The woolly hairs are not found typ- 

 ically on the face, or on the hands and feet. These two sorts of hairs 

 are not sharply defined types and many individual hairs are seen which 

 are intermediate between the two. 



The basal half or a little more of the woolly hairs is of a general 

 slate-gray or almost plumbeous color, darker on the hairs of the back 

 and lighter on those of the belh\ Normally, this slaty color is never 

 seen in the upper parts except on parting the thick coat, but on the 

 underparts where the hairy covering is less dense a certain amount of 

 the slaty or plumljeous color shows through. The distal half of the 

 woolly hairs is about equally divided between two colors, a grayish or 

 yellow-gra}" color next the slaty basal color, and terminally some sort 

 of an ochraceous or buffy color, to which the general color of the 

 animal is due. On the dark face marks when present and along the 

 dorsal stripe the terminal color of the hairs is much darker, varying 

 from a light, bright russet to a very dark brown. 



The long straight hairs have little to do with the real general color 

 effect. They seem to be very similar in color to the woolly hairs 

 except at the tip, where there is a large white subterminal ring about 

 3 to 5 mm. wide. The apical ring is about 1 to 2 mm. wide and dark 

 in color, which is not seen ordinarily and has no effect on the general 

 color. The subterminal white ring, however, often apparently enters 

 very largely into the general color scheme, and in case the hairs are 

 long and their tips not worn produces a conspicuous frosting overly- 

 ing the general ochraceous color of the upper parts. This frosted 

 effect is most conspicuous in two specimens of Xydlcehus jnalaianus, 

 a two-thirds grown individual. Cat. No, 84390, U.S.N.M., from Trong, 

 Lower Siam; and a young adult male. Cat. No. 114151, LT. S.N. M., from 

 JohoreLama. In an adult of unknown sex. Cat. No. 843S'J, U.S.N.M., 

 from Trong, no frosting' at all is present except a very slight amount 

 on the upper part of the neck. Except for a few hairs on either side 

 of the dark median stripe no frosting is seen in Cat. No. 142233, 

 U.S.N.M., a young adult male from western Borneo. An adult male. 

 Cat. No, 142234, U.S.N.M., also from western Borneo, shows nearly 



