14 GYLDENSTOLPE, ON A COLLECTION OF MAMMALS MADE IN EASTERN AND CENTRAL BORNEO. 



parts of the body. The lower parts of the body, the arms, the legs and the tail 

 are exactly of the same colour as in the Perak specimen, but in this latter the black 

 hairs radiating from the forehead are more numerous and the black frontal line thus 

 more well-marked. In his »Monograph of the Primates» (part II, p. 232) Dr. Elliot 

 states that there are three specimens of M . irus irus in the British Museum Natural 

 History collected at the Baram District in Sarawak. It therefore seems that the 

 common form of the Crab-eating Monkey also inhabits Borneo, and Elliot's M. 

 irus mandibularis may than only be founded on individual variation. 



Skull measurements (for comparison the measurements of a typical female spe- 

 cimen of M. irus irus from Perak are also recorded. Both the specimens are of 

 about the same age). 



9 Borneo 9 Perak 



Greatest length of skull 97,2 mm. 97,6 mm. 



ConHylobasal length of skull 75,1 » 74,3 » 



Basicranial length of skull C9,2 » 67,6 » 



Oecipitonasal length 81,8 » 82,5 » 



Zygomatic width 63,3 » 67,2 » 



Greatest width of brain-case 49,5 » 52,2 » 



Least interorbital width 3,0 » 4,0 



Least postorbital width 38,2 » 38,4 » 



Length of palate from henselion 42,8 > 41,8 » 



Length of upper toothrow (front of c. to back of m 3 ) 31,2 » 31,9 » 



Length of upper molar series 25,9 » 26,5 » 



Length of lower molar series 31,2 » 31,3 » 



7. Macaca irus mandibularis Elliot. 



Proc. U. S. Nat. Mus. vol. 38, 1910, p. 347. 



No. 3. $ Kaboreau, Eastern Borneo fl /i 1914. Head and body: 469 mm. Tail: 528 mm. Hindfoot: 

 128 mm. Ear: 32 mm. 



This form is very similar to the typical Macaca irus irus Cuv. from the Malay 

 Peninsula. It is said to differ by being more tawny ochraceous on the top of the 

 head and ochraceous buff above. These characters agree well with the specimen in 

 the present collection. The typical M. irus irus, however, undergoes a considerable 

 amount of variation and one female specimen from Perak is fairly similar to the 

 Bornean animal, which, however, is brighter. The lack of material for the present 

 time makes me to refer the Bornean animal to the race described by Elltot, but 

 I think it is most certain only based upon individual variation, and therefore not 

 valied as a distinct race, as there are no cranial differences to be noticed. 



Skull measurements: Greatest length of skull: 100,6; cond}'lobasal length: 74. o; 

 basicranial length: 67,2; oecipitonasal length: 85,5; zygomatic width: 65,o; greatest 



