26 MAMMALIA ORDER L PRIMATES. 



times a female would be seen carrying a young one on its back, to which it 

 clung with legs and tail, the mother making its way among the branches, 

 and leaping from tree to tree, apparently but little encumbered by its 

 baby." 



The beautiful little squirrel-monkeys are the first representatives of a third 

 sub-family of the Cebidce, which, while agreeing with the last in the vertical 

 position of the incisor teeth, and the normal conforma- 

 Squirrel- tion of the hyoid bone, are distinguished by the tail, which 

 Monkeys is long, having no power of prehension. In all the thumb 

 (Chrysothrix). is well developed. From the allied forms the squirrel- 

 monkeys, or sairniris, are specially distinguished by the 

 soft, close, and erect fur, and the backward production of the head ; the 

 face beingf relatively small, the eyes very large and set close together, the 

 partition between the nostrils very wide, and the rather long tail covered 

 with comparatively short hair. There are four species of the genus, of 

 which the common squirrel-monkey (Chrysothrix sciureus) is the type. 

 These monkeys are some of the commonest of their tribe in America, where 

 they range from Costa Rica to Brazil and Bolivia. In habits they are 

 diurnal, feeding chiefly upon insects, although they will also kill and eat 

 the smaller birds. 



The eleven representatives of this genus form a group which is to a 

 considerable extent intermediate between the squirrel-monkeys and the 

 under-mentioned douroucoulis. From the former the small 

 Titis head is distinguished by not being produced backwards, and 



(Catttthrix). the small size of the eyes ; but the nostrils are similar in the 

 width of the partition by which they are separated, and the 

 fur has the same close and soft texture. The tail is, however, bushy, and 

 the canine teeth are relatively small, while the angle, or hinder extremity, 

 of the lower jaw is expanded somewhat after the same fashion as in the 

 howlers, although to a smaller degree. The titis range from Panama to the 

 southern limits of the great forests ; a well-known species being the white- 

 collared titi (Callithrix torquatci). In habits, they are very similar to the 

 squirrel-monkeys ; insects, eggs, and small birds constituting their chief 

 nutriment. 



From both the preceding genera the small monkeys commonly known as 

 douroucoulis are distinguished by their nocturnal habits and the great size of 

 the eyes, which are only separated from each other by a very 

 Douroucoulis narrow partition. The head is rounded, and the nostrils 

 (Nyctipithecus). are placed closer together than in either of the allied genera; 

 the moderately long tail being bushy, and the fur soft and 

 close. In colour the eyes are yellowish, and they have a peculiar stare, com- 

 municating, in conjunction with their large size, a somewhat owl-like expres- 

 sion to the whole face. There are five species of the genus, several of which, 

 like the three-striped douroucouli (Nyctipithecus trivirgatns\ have three more 

 or less distinctly defined longitudinal dark stripes running down the forehead. 

 The range of the douroucoulis extends from Nicaragua to the Amazoa and 

 Eastern Peru. During the daytime, these somewhat lemur-like monkeys 

 remain snugly coiled away in the holes or among the branches of trees, and 

 only issue forth at night in search of prey. When on the prowl, they give 

 vent to loud howls or cat-like cries ; and their food includes insects, birds, and 

 fruits. In constitution they are extremely delicate, only surviving capture 

 for a brief period. 



