96 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



mucous fluid excreted during oviposition. From two to five hours 

 are required for this operation, and an average of three of these 

 masses is deposited during a period of from six to eight weeks. 



As the time of ovipositing varies with the latitude, so the 

 hatching of the eggs occurs from the middle or last of March 

 in Texas till the middle of May or first of June in Minnesota 

 and Manitoba. Until after the molt of the first skin, and often 

 till after the second or third molt, the young nymphs are con- 

 tent to feed in the immediate vicinity of their birth. When 

 the food becomes scarce they congregate together and in 



FIG. 63. Rocky Mountain locusts: a, a, a, females in different positions, 

 ovipositing; b, egg-pod extracted from ground, with end broken open; 

 e, a few eggs lying loose on ground ; d, e, show the earth partially removed, 

 to illustrate an egg-mass already in place and one being placed; / shows 

 where such an egg-mass has been covered up. (After Riley.) 



solid bodies, sometimes as much as a mile wide, march across 

 the country, devouring every green crop and weed as they go. 

 During cold or damp weather and at night they collect under 

 rubbish, in stools of grass, etc., and at such times almost seem 

 to have disappeared; but a few hours of sunshine brings them 

 forth, as voracious as ever. When, on account of the immense 

 numbers assembled together, it becomes impossible for all to 

 obtain green food, the unfortunate ones first clean out the 

 underbrush and then feed upon the dead leaves and bark of 

 timber lands, and have often been known to gnaw fences and 



