304 COMPARATIVE ZOOLOGY. 
toes, and one or two of the fingers, are armed with hook- 
ed nails. The clavicles are remarkably long, and the ster- 
num is of great strength; but the whole skeleton is ex- 
tremely light, though not filled with air, as in Birds. The 
Fig. 330.—Skeleton of a Bat. 
eyes are small, the ears large, and the sense of touch is 
very acute. The favorite attitude of a Bat when at rest 
is that of suspension by the claws, with head downward. 
They are all nocturnal. 
7. Cetaceans, or Whales, have the form and life of Fish- 
es, yet they possess a higher organization than the preced- 
ing orders. They have a broad brain, with many and 
deep foldings; the foramen magnum of the skull is en- 
tirely posterior; the whole head is disproportionately 
large, and the jaws greatly prolonged. The body is cov- 
ered with a thick, smooth skin, with a layer of fat (“ blub- 
Fic. 331.—Outline of the Sperm-whale (Physeter): a, blow-hole; b, the case contain- 
ing spermaceti; c, junk; d, bunch of the neck—between it and the corner of the 
mouth is the eye; h, hump; 7, ridge; &, the small; J, tail, or flukes. Between 
the dotted lines are the spiral strips of blubber. Maximum length, sixty feet. 
South Atlantic. 
