SAIMIRI 317 



nape black : shoulder and outer side of arms to below elbows, and legs 

 to ankles gray washed with yellow ; upper parts dark ochraceous 

 rufous, dorsal line dark orange rufous ; throat and between arms 

 white, rest of under parts and inner side of limbs ochre yellow ; hands 

 and feet ochraceous ; tail above for two thirds the length black and 

 yellow, beneath yellow, apical portion black. 



Meastiremetits. Total length, 633 ; tail, 363 ; foot, 78 ; ear, 24. 

 Skull: occipito-nasal length, 56; zygomatic width, 36; intertemporal 

 width, 30; palatal length, 15; breadth of braincase, 35; median length 

 of nasals, 8: length of upper molar series, 11 ; length of mandible, 31 ; 

 length of lower molar series, 13. 



This species was originally described from an example obtained 

 at Chiriqui, and Dr. Frantzius states it is confined to the hotter region, 

 being very abundant in the valley of Terraba and on the plain of Piris, 

 and he believed its northern limit to be the spurs of the Herradura 

 Mountains going towards the sea. A living individual was presented 

 to the London Zoological Society by Mr. W. F. Kelley, who said it 

 was procured in the Department of Solala, Guatemala, but no other 

 example seems to have come from there and it is surmised that possibly 

 Mr. Kelley's animal may have been brought from some southern 

 locality. 



Mr. Thomas has described the monkey from Pozo Azul, Costa 

 Rica (1. c.) as a distinct race under the name of 6". ccr. citrinellus, the 

 chief character being the head "less blackened and the limbs less yel- 

 low." A series of these monkeys from Panama collected by J. H. 

 Batty and two specimens from Pozo Azul collected by M. A. Carriker, 

 belonging to the New York Museum of Natural History are before 

 me. In the Panama series every style of head coloring from jet black 

 to gray is represented, some almost exactly like the examples from 

 Pozo Azul, and the difference in coloration would seem to be due to 

 age, the old adults having intensely black crowns, and this passing 

 through all grades of coloring to the young animals with little or no 

 black on the head. The type of 5". cer. citrinellus in the British Museum 

 has less black on the head than the old adults, and it does not go so 

 far on the occiput, but other specimens from the same localities in the 

 Museum collection have black crowns, and it does not seem that a dis- 

 tinct race can be sustained, knowing, as we do, the great diversity of 

 head coloring that exists at different periods of the animal's existence. 

 I have therefore placed i". ccr. citrinellus as a synonym of S. cerstedt. 



