SAPAJOUS. 157 



distinguished from the sapajous. A more important point of difference is, however, 

 to be found in the naked skin on the under part of the end of the tail a character 

 in which these monkeys resemble those of the next two genera. The woolly 

 monkeys have, however, the same robust build as the sapajous, and thereby differ 

 from the other members of this group of genera. They have well-developed 



HUMBOLDT'S WOOLLY MONKEY (J nat. size). 



thumbs. The great length of the tail in the woolly monkeys, together with its 

 naked tip, render it a prehensile organ of the most perfect type. 



To the Portuguese colonists of Brazil these animals are known as Macaco Bar- 

 rigudo, frequently abbreviated into Barrigudo ; the full name signifying " big- 

 bellied monkey," and being applied to them in allusion to their bulky build, as 

 contrasted with the slender form of their cousins the spider-monkeys. The ordinary 

 form of Humboldt's lagothrix has a general blackish-grey colour, with the head, 

 chest, under - parts, and tail black. The individual hairs are dark grey, with 

 very short black tips, on those parts of the body which are not black. Younger 



