230 Mr. 0. Thomas on 



appears to be fractureJ near its termination, where it indi- 

 cates a pulp-cavit3', though the inner and outer walls are 

 compressed close together. The roots are about 1 millim. 

 wide. Notwithstanding a certain resemblance in form of the 

 interspace between the roots to the form of the crown, I do 

 not see any ground for affirming that it has been produced 

 by absorption. It is, however, certain that the character is 

 an abnormal one, since it is absent from the other isolated 

 teeth, and its chief interest consists in showing that it is 

 possible for a reptile to develop roots to a tooth of the 

 mammalian molar type ; so that if this abnormal condition, 

 seen in Nufhetes, were normal and general in a fossil jaw, it 

 would constitute an important deviation from the reptilian 

 dentition. 



The figure is ten times natural size. 



XXXVIII. — Descriptions of Two ne.w North-Bornean 

 Mammals. By Oldfield ThOMAS. 



[Plate VII.] 



Semnopithecus sabanus, sp. n. (PL YII.) 



Bodj, arms and legs, and tail grey; hands and feet black, 

 as in the group to which S. Hosei, S. Everettt\ and ;S'. Thomasi 

 belong. 



Forehead with a high median black crest, commencing 

 immediately behind the centre of the brow-ridges; the hairs 

 of the crest stand up vertically and are about an inch and a 

 half in length. Eyebrow-bristles long, black, projected 

 forwards over the eyes; behind them, on each side of the 

 central crest, the forehead-hairs lie back flat against the head 

 and are whitish in colour over the whole crown. Outside 

 these whitish patches, again, the sides of the face, from the 

 orbits to the ears, are quite black, and the hairs of the occiput 

 are also decidedly darker, especially terminally, than are 

 those of the pale frontal patches. It results from this arrange- 

 ment of the colours that on looking down vertically on the 

 crown one sees a pale frontal area, bisected mesial ly by the 

 blackish crest and surrounded on all sides by black, in front 

 by the black eyebrows, laterally by the black temples, and 

 posteriorly by the black tij)ped occipital hairs. These crown 



