562 
MAMMALIA. 
number of exercises, serious or burlesque, which they execute 
with imperturbable coolness and comical gravity. 
In ordinary circumstances the voice of the Sapajous is soft, 
and somewhat like that of the Ateles ; but under the influence 
of excitement, either anger or pleasure, it is the reverse. When 
teased, it emits a kind of plaintive wailing, which has obtained 
for it the name of Weeper Monkey. They have also been desig- 
nated Musk Monkeys, in consequence of the musky odour they 
exhale. With regard to the denomination of Sajou, which is 
sometimes employed, it is simply an abbreviation of Sapajou. 
It is difficult to ascertain the number of species of Sapajous, for 
Fig. 248. — The Sai ( Cebus capuclnus). 
there exists an infinite variety of them, and it is rare to meet two 
individuals which are exactly alike. Naturalists are, therefore, 
greatly divided on this point, some taking for distinct species what 
others will only admit to be varieties. Is. Geoflroy Saint-Hilaire 
has described fourteen species of Sapajous, divided into special 
groups, according to their having the hair on the head lying 
smoothly, disposed like a brush, or standing on end, erect like a 
plume, or arranged in a circular tuft. The most common are the 
Brown Sapajou, the Sai (Fig. 248), and the Capuchin. In 
Paraguay an Albino of this latter species is found ; it is a noc- 
turnal animal, which cries in the most lugubrious manner during 
starry or moonlit nights. 
