QUADRUMANA. 105 



perfect state, but distinctly marked, by their nostrils 

 being separated by a narrow partition, and opening 

 nearly beneath the nose. After these we find 



Lagothrix, or Gluttonous Monkeys, having the 

 head round like Ateles^ the thumbs as in the How- 

 lers, and the tail partly marked as before ; the limbs 

 are moderately long, and the hair is rather woolly. 

 Then comes the genus 



CEBUS, SAJorJs, or Weepers, properly so called, 

 with rounded heads, but their tails entirely hairy, 

 though still prehensile. A group of these animals 

 have the hair of the forehead disposed in tufts, and, 

 therefore, are known as the horned weepers. 



In the second sub-tribe (Chalanura) or with tails 

 depressed, imperfectly prehensile, or absolutely lax 

 and bushy ; the hands always pentadactylous : we 

 first meet with the genus 



CALLITHRIX, or Squirrel Monkeys, with round 

 heads; eyes and ears large ; tail longer than the body, 

 covered with short hair; nails flat on the thumbs, long 

 and narrow on the fingers. And next to these, 



PMecia, or Fox Tails, with eye and ears resem- 

 bling those of man ; strong canines, and tails usually 

 long and brush-like. A sub-division of this group 

 have, by Spix, been formed into another genus, un- 

 der the name of 



BRACHYURUS, because they have tails in length 

 less than the body. These genera begin to be noc- 

 turnal, or at least crepuscular ; they reside in the 

 deepest forests, and we have observed them at the 

 dawn of day, in the summits of the highest trees, 



