44 PYGATHRIX 



95.7; occipito-nasal length, 87; Hensel, 63.5; zygomatic width, 72.2; 

 intertemporal width, 43 ; palatal length, 28.4 ; median length of nasals, 

 10 ; length of upper molar series, 24.9 ; length of mandible, 66.3 ; length 

 of lower molar series, 27.1. 



This form differs from P. chrysomel.\s, in having on the upper 

 parts various tints of brown instead of black, according to the indi- 

 vidual or sexual peculiarities of examples, and the throat and chest 

 black not brown. Each kind represents a fairly distinct island species. 



Pygatheix batuana (Miller). 



Presbvtis batuanus ( !) Miller, Miscel. Coll. Smith. Instit., Wash., 

 1903, p. 670. 



Type locality. Pulo Pinie, Batu Islands. Type in United States 

 National Museum. 



Genl. Char. Similar to P. sumatrana but smaller, tail shorter, 

 and white at root beneath. 



Color. General hue black, with crown and back washed with 

 brownish; inner side of thighs, belly, median line of chest grayish 

 white ; tail above like body, beneath grayish white at root, grading 

 into black at tip. Ex type United States National Museum. 



Measurements. Total length, 1,150; tail, 665; foot, 163. Skull: 

 greatest length, 912; occipito-nasal length, 80.8; zygomatic width, 

 70.5; Hensel, 58.5; intertemporal width, 40.7; palatal length, 28.6; 

 median length of nasals, 11.7; length of upper molar series, 22.9; 

 length of mandible, 62.5 ; length of lower molar series, 28.4. Ex type 

 United States National Musetun. 



This species differs from its ally, P. sumatrana, in having a 

 smaller skull, with shorter slighter canines, and quite a different 

 mandible, this being very broad at the angle, and the ascending ramus 

 is also very wide and with a deep lateral pit ; the mandible of the 

 Sumatran form being rather light and slender, and with a narrow 

 ascending ramus, its anterior edge much curved outwardly and then 

 backward, ending in a point. In body and limb measurements the two 

 differ much. 



Pygathrix percuka (Lyon). 



Presbvtis percura Lyon,*Proc. U. S. Nat. Mus., XXXIV, 1908, 



p". 671. 

 Type locality. Kompei, eastern Sumatra. Type in United States 

 National Museum. 



