SPECIES OF MAMMALS OF THE PACIFIC AREA 71 



forms have been divided into nine groups which differ from one 

 another chiefly in skull characters. Externally they are also 

 characterized by the direction of the hair on the crown and 

 sides of the head. The nine groups are : femoralis, chrysomelas, 

 melalopha, thomasiy aygula, hosel, rubicunda, frontata, and 

 pyrrhus. 



In the femoralis group, the hair on the crown rises to a high 

 thick crest. A whorl of hair appears about an inch behind the 

 brows and a fringe of hairs above the brows. There are only 

 three races of this leaf monkey found within our limits, two of 

 which occur on the Rhio Archipelago and one in the Natuna 

 Islands. These monkeys are all light brown above, with the 

 outersides of the thighs grayish and the entire underparts white. 

 A white patch shows on the temple behind the eye. In the race 

 found on Bintang Island (rhionis) the bases of the hairs on the 

 forehead and crown are brown, while in the animal inhabiting 

 Kundur Island (canus) the same hairs have gray bases. The 

 race on the Natuna Islands (natunce) is darker brown above, 

 with blacker limbs and a smaller white patch on the temple, sur- 

 rounded by black. 



In Borneo, the chrysomelas group occurs. It is distinguished 

 by a pair of whorls on the forehead with crest similar to the 

 femoralis group, and by the lack of the fringe over the eyes. In 

 typical chrysomelas of Sarawak the color is similar to that of 

 femoralis but blacker, and the lower side of the tail is white for 

 the greater part of its length. From the vicinity of the Miri 

 River yet a second form (crucifer) is known. This animal is 

 black and red: the crown, flanks, and outer surfaces of the legs 

 are red, while a black band extends from the nape along the back 

 and down the arms. This may be a color variety of chrysomelas. 



The third group of the leaf monkeys, melalopha, is charac- 

 terized by the absence of a fringe over the eyes and by the pres- 

 ence of a definite whorl of hairs on the forehead. The hairs grow 

 mainly backward from the brow to form a crest on the crown. 

 The melalopha group is restricted to Sumatra and the Batu 



