372 



ELEMENTARY BIOLOGY 



or of a group, rather than to the protection of the individual. 

 This is seen in the constructions of such animals as the 



FIG 191. Praying mantis 



This animal lies in wait for its prey with the front legs raised in a manner suggesting 



the attitude of prayer. It catches small insects with its strong front legs. Large species 



living in the tropics have been known to kill small birds 



beaver or the prairie dog (Fig. 189), in the hutch of the rabbit, 

 in the diggings of the mole, and in the nest of the mouse. 



FIG. 192. The ant lion 



a, adult ; l>, larva ; 1; larva covered with dirt ; c, incased pupa ; d, pit in sand. The larva 



buries itself in loose sand at the bottom of a small pit. Ants and other small crawling 



insects tumble into the pit and are seized by the strong jaws of the ferocious " lion " 



412. Fighting. Nothing would seem to be more helpless 

 and less offensive than the soft-bodied jellyfish ; the very name 



