VERTEBRATA. 331 
arate, clawed toes and no incisors. The Sloths are arbo- 
real; the others burrow. ‘The brain is generally smooth; 
a= = Laie = i = 
( Rus pare STU 
= 
Typo 
Fie. 324.—Armadillo (Dasypus). 
but that of the Ant-eater is convoluted, and has a large 
corpus callosum; but in all, the cerebellum and part of 
the olfactories are exposed.” 
4, Rodents, or Gnawers, are characterized by two long, 
curved incisors in each jaw, enameled in front, and per- 
petually growing; they are specially formed for nibbling. 
Separated from them by a wide space (for canines are 
wanting), are the flat molars, admirably fitted for grind- 
Fig. 325,—Skull of a Rodent (Capybara): 22, premaxillary; 21, maxillary; 26, mo- 
lar; 27, squamosal; 73, lachrymal; 15, nasal; 11, frontal; 4, occipital processes, 
unusually developed; ¢, incisors; a, angle of lower jaw. 
