256 CALLICEBUS 



p. 229; V, 1855, p. 110; Tschudi, Faun. Peruan., 1844, p. 46- 



I. Geoff., Cat. Primates, 1851, p. 40; Wallace, Proc. Zool. Soc. 



Lond., 1852, pp. 107-109; Dahlb., Stud. Zool. Fam. Reg. 



Anim. Natur., fasc. I, 1856, pp. 153-155 ; Reichenb., Vollstand. 



Naturg. Affen, 1862, p. 21, figs. 54-55 ; Mivart, Proc. Zool. 



Soc. Lond., 1865, pp. 555-584; Gray, Cat. Monkeys, Lemurs 



and Fruit-eating Bats, Brit. Mus., 1870, p. 56 ; Schleg., Mus. 



Pays-Bas, Simiae, 1876, p. 231. 

 Simla (Callithrix) personatus Humb., Rec. Obs. Zool., I, 1811, 



(1815), p. 357. 

 Pithecia melanops Vig., Cat. Coll. Zool. Soc. Lond., p. 6. 

 Cebus personatus Blainv., Osteog., 1841, Atl., Cebus, pi. VI; Less., 



Nouv. Tabl. Reg. Anim., 1842, p. 87. 

 Saguinus personatus Less., Spec. Mamm., 1840, p. 162. 



MASKED TITI MONKEY. 



Type locality, "le Bresil." Type unknown. 



Geogr. Distr. Region of the Upper Amazon, south to latitude 

 14°. 



Genl. Char. Head to behind ears, and throat black. 



Color. Male. Face naked, black; head to behind ears, throat, 

 hands and feet black; nape yellowish white; back pale reddish brown 

 becoming a bright hazel on the rump ; limbs cream buff tinged with 

 gray ; chest orange rufous, passing into blackish brown on abdomen ; 

 tail burnt sienna red. 



Female. Head and throat black like the male; nape, upper part 

 of back and arms yellowish white ; middle of back russet grading into 

 a reddish brown on rump ; flanks and legs grayish white ; center of 

 abdomen pale ochraceous rufous, sides grayish white. 



The males vary greatly in coloring even in the same locality, and 

 some have the upper part of back and arms whitish yellow like the 

 nape, or a dark brownish gray, with lower back and rump dark grayish 

 brown, or reddish brown with the under parts uniform dark grayish 

 brown. 



The female is therefore much paler than the male, with a reddish 

 brown back. 



Measurements. Skull : occipito-nasal length, 70 ; Hensel, 55 ; 

 zygomatic width, 49 ; intertemporal width, 35 ; palatal length, 23.5 ; 

 breadth of braincase, 37; median length of nasals, 11; length of 

 upper molar series, 18 ; length of mandible, 52 ; length of lower molar 

 series, 20. 



