g 2 ZOOLOGICAL SKETCHES. 



up, as if unwilling to interfere with your locomotive 

 facilities. 



Judging from the size of his claws, it would seem that 

 he might use them in a pluckier way ; but after a closer 

 examination the sloth can hardly be blamed that discre- 

 tion should be largely the better part of his valor. His 

 equipment for the struggle of existence evinces, indeed, 

 an almost unfair and certainly unparalleled parsimony 

 on the part of our all-mother Nature. The Bradypus 

 tardigradus has only three toes on each foot and two 

 ringers per hand, making a total of ten claws, to the 

 squirrel's eighteen and the bear's twenty; his legs are 

 so stiff that they can only be laterally extended, and 

 so awkwardly curved that the knees cannot be brought 

 together, thus making his movements on a level surface 

 as hobbling as those of a sprained bat. His molars are 

 very poorly developed, being merely attached to the ex- 

 terior gums, without roots and without enamel, while 

 the bicuspids, canines, and incisors are entirely wanting. 

 The tail is stumpy or absent, the jaws short, the skull 

 flat and truncated. His eyes are small, and, like his 

 ears, almost buried in tufts of coarse, wiry hair. In 

 short, the sloth is a creature with the vertebrate ground- 

 work of a mammal, but sadly stinted in the " sizings" of 

 nearly all his complementary organs. 



The school of Antisthenes, however, demonstrated 

 that a reduction of our wants is virtually equivalent to 

 an enlargement of our means; and, by pursuing this 



