THE CAPUCHINS. 205 
Man-like of all the Apes; in some species the nails of the 
digits are compressed laterally. 
In the “Skull the cranial portion exceeds the facial. 
Professor Mivart observes that in this group the facial part 
is relatively smaller than in many of the higher Old World 
Apes. ‘The skull has no external bony canal (or meatus) to 
the ear; and its frontal bones possess large air-cavities. In the 
Capuchins the incisor teeth are erect, and are always shorter 
than the canines. The molars are four-cusped, and have, on 
their crowns, two transverse ridges andthe oblique ridge, already 
described in the Lemuvordea, from the front inner cusp to the 
hind outer cusp. ‘These animals have also one milk-molar tooth 
more than in Man. 
The outer surface of the main brain (cerebrum) is almost as 
much convoluted as in the Old World Apes. 
The Capuchins range from Costa Rica to Paraguay, and are 
represented by about eighteen species. They are very gentle 
and docile animals. 
F. Cuvier observes in his ‘ Histoire Naturelle des Mam- 
miferes,” that of all the Quadrumana—indeed, of all the 
Mammals—there are none so difficult to characterise as the 
Capuchins of America, whose colours vary almost with every 
individual. No two authors agree in the number of species 
the genus contains. Brisson recognised three, Linnzeus four, 
Gmelin six, Buffon two, and George Cuvier supposed it possible 
that they all belonged to but one species. Two causes help to 
produce this diversity of opinion ; one is, as remarked above, 
the natural disposition which these animals have to vary, and to 
become lighter or darker in colour according to circumstances, 
and the other is the extremely close relationship that exists 
between the different species of the genus. Observations, how- 
