THE ANIMAL FOOD OF BIRDS. 



43 



into young, which resemble in a general way the adults. 

 These young 'hoppers feed upon grass, clover, and similar 

 plants, increasing gradually in size and occasionally shedding 

 their skins. - In the course of about two months they acquire 

 wings and become full grown. The Rocky Mountain locusts 

 develop normally on the high, dry table-lands of the Rockies 

 and occasionally migrate in vast numbers to the fertile fields 

 of the Mississippi Valley. The red-legged locust is the most 

 abundant of the widely dis- 

 tributed species of this family. 

 These insects form a large 

 part of the food of nestling 

 birds as well as of the adults. 



The family Locustidce, which 

 includes the long-horned grass- 

 hoppers and katydids, is at 

 once distinguished from the 

 Acridiidce by the very long an- 

 tennae. These insects are also 

 of much less economic impor- 

 tance, but some species occa- 

 sionally become seriously injurious. They are often preyed 

 . upon by birds, both in the vgg and mature states, the latter fre- 

 quently being fed to nestlings, and with some species of birds 

 they form a comparatively important element of food. 



The crickets, belonging to the family Gryttidce, are abundant 

 everywhere in fields and meadows, and probably do consider- 

 ably more damage than they are usually accused of. In the 

 Northern States the common black species usually winters 

 over in the condition of the egg, although a few manage to 

 come through in a partially grown state. Their eggs are 

 deposited in the ground by means of the long pointed ovi- 

 positor of the female. The climbing or tree crickets of the 

 genus (Ecanthus are perhaps the most injurious members of 

 the family. They deposit their eggs in the canes of the rasp- 



STAGES OF THE ROCKY MOUNTAIN I.01TST. 

 (After Urieii.) 



