LIFE ON THE EARTH. 41 



toral fins. Pterodactylus, by its large and pointed 

 wings, retractile neck and snapping long-toothed 

 jaws, seems to realize all that can be supposed of a 

 reptile accustomed to flap the air rather heavily not 

 far above shallow waters, and occasionally to snatch 

 from them fishes swimming near enough to the sur- 

 face to come within reach. 



Life in Trees presents us with a considerable 

 variety of contrivances for holding to the surface, 

 grasping the branches, or making incisions into the 

 bark and wood. To say nothing of the sucker 

 feet of Dipterous Insects, and the Gecko Lizard, we 

 may remark on the prevalent idea of climbing and 

 holding on by opposable fingers which appear among 

 the Reptilia in Chamseleon, among the Birds in the 

 Parrot and Woodpecker, and among the Mammalia 

 in the whole race of the Quadrumana. Perhaps the 

 prehensile tail of the Platyrhine Monkeys, and the 

 suspensorial claws of the Sloth, may be quoted 

 among the singular provisions of animals of the New 

 World. It is even more curious to notice with re- 

 spect to some of these climbing animals, the other 

 adjustments which complete their equipment. Thus 

 the feeding of the Woodpecker is provided for not 

 only by its scansorial foot, its supporting tail, and 

 its perforating beak, which makes the forests ring 

 around. We have further to notice the singular 



