254 



AN INTRODUCTION TO ENTOMOLOGY 



Subfamily LOCUSTIN^ 



The Spur-throated Locusts 



The members of this subfamily are distinguished from other 

 North American locusts by the presence of a tubercle on the pro- 

 sternum. Here belong 

 many of our more com- 

 mon species; and among 

 them are found the most 

 injurious insects of the 

 order Orthoptera. Among 

 our best -known species 

 are the following. 



The Rocky Mountain 

 locust or western grasshopper, Melanoplus spretus. — The most terrible 

 of insect scourges that this country has known have been the invasions 



Fig. 277. — Side view of a female locust with the 

 wings removed. 



Fig. 278. — Egg-laying of the Rocky Mountain Locust : a, a, a, female in different 

 positions, ovipositing; b, egg-pod extracted from the ground with the end 

 broken open; c, a few eggs lying loose on the ground; d, e, show the earth 

 partially removed, to illustrate an egg-mass already in place, and one being 

 placed; / shows where such a mass has been covered up. (From Riley.) 



of this species. Large areas of coimtry have been devastated, and the 

 inhabitants reduced to a state of starvation. The cause of all this 

 stiff ering is not a large insect. It is represented in natural size by 

 Figure 278. It measures to the tip of its 

 wing-covers 20-35 mm., and resembles 

 very closely our common red-legged lo- 

 cust, the most abundant of all our species. 

 It can easily be distinguished from this 

 species by the greater length of the wings, 

 which extend about one-third of their 

 length beyond the tip of the abdomen, 

 and by the fact that the apex of the last 

 abdominal segment in the males is distinctly notched. 



Fig. 279. — Melanoplus femur- 

 rubrum. 



