CLASS I. Mx\MMALIA: ORDER 2. QUADRUMANA. 
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them. They live on insects, and especially spiders, which they catch with admirable dexterity 
alike with their hands and their lips. 
The species of this genus are the Tee-tee, or Squirrel Monkey, S. sciureus^ of Guiana and 
Brazil ; the S. ustus, of Brazil ; and the S. entomojjJiaffus, found in troops in Bolivia and Peru. 
M. Geoifroy mentions another species under the name of the Orinoco Ti-ti, >S'. hmulahis. 
Genus NYCTIPITHECUS : JVijctipithccus. — These are about ten to twelve inches long, and are 
distinguished by a large round head, and eyes that give out phosphorescent light in the darkness. 
They sleep by day and are active at night, and hence are called JVocthores, or Night Monkeys, by 
French authors. They live in hollow trees, and do not gather in bands. They are found in Brazil. 
THE BOUROUCODLI. 
The best known of this genus is the Douroitcouli Monkey, JV. trivirgatus. Its general color is 
gray : its body and head measure ten inches. It lives on the borders of the Orinoco, and is noc- 
turnal in its habits. It is sad of aspect, and solitary in its disposition. It passes the day in sleep, and 
