152 TRANSACTIONS OF THE 



carcasses, and will even devour one another. Their cannibalism is 

 corroborative of Darwin's famous law — the survival of the strongest. 

 When all else is gone the ravenous creatures fix eager eyes upon one 

 another, twirling their antennte about like the tail of a cat when 

 watching for mice, and the moment an individual reveals signs of 

 weakening or fear, its neighbors pounce upon it and devour it 

 wholly. 



Very interesting is the natural history of the Rocky Mountain locust. 

 If it were not the horrid looking and dreadful destroyer it is, its habits 

 and instincts, fully narrated, would be as enchanting as a romance. 

 Their life is spanned by a few summer months, none living over the 

 winter. Having a permanent locality where more or less of them 

 may be found every year, favoring conditions allow them to occa- 

 sionally become numerous — too numerous for the commissariat. For 

 days they assemble in vast herds. All is stir and eager prepara- 

 tion. Frequentlj^ they rise, circle round and round, rising perhaps 

 until out of sight, then suddenly dropping like plummets to the 

 ground. The direction of the upper currents was unfavorable. When 

 the wind favors their plans, they embark upon it for days together, 

 sometimes alighting at night, but as often continuing night and day 

 in an air line, always in the direction of choicest food, though it may 

 be hundreds or a thousand miles away. Often they ascend so high as 

 to be invisible, and this accounts for their unwarned presence some- 

 times in distant lands. Swarms have been noted as flying in different 

 directions and even in opposite directions, scurrying along on different 

 strata of air. 



Their flight may be likened to a snow storm extending from the 

 ground to a height at which our visunal organs perceive ihem as only 

 minute, darting scintillations. " When on the highest peaks of the 

 snowy range, 14,000 to 15,000 feet above the sea," writes Mr. W. M. 

 Byers, " I have seen them as much higher as could be distinguished 

 by a good field glass." If they meet with adverse winds they 

 instantly fold their wings and fall to the ground, and lie in heaps 

 until favorable winds allow them to proceed. If the favoring breeze 

 veers around a few points across their course they tack too, and move 

 sidewise; when the favoring wind becomes a gale they turn head 

 toward it, using their wings vigorously, and so are carried along at a 

 much less rate than that of the gale. Does the sailor on the great 

 deep display greater skill in navigation? Arrived at the chosen 

 fields, they come to a halt, and trouble begins. They convert a corn- 

 field in a few hours into a stretch of bare spindling stalks. Covering 

 each hill by hundreds, scrambling from row to row like a lot of hun- 

 gry pigs, their sharp jaws gnashing with the noise of a thousand 

 shears, they devour the crop quicker than could a herd of hungr}^ 

 steers. After supper comes a rest with most animals. Not so with 

 locusts. Where they eat, there at once the sexes unite, and the 

 female hurries off to find a suitable place for depositing her eggs. 

 The sexual habits and the description of egg-laying, the hatching, 

 moting, and travels of the young, will be considered in another par- 

 agraph. As stated, egg-laying always takes place wherever invading 

 swarms feed. The next spring the young are hatched, and are born 

 hungry. Often so thick as to blacken the ground, they move like 

 sea waves over the meadows, devouring every green thing ; eating the 

 roots of grasses closer than did their predecessors; only stopping in 

 the coolest hours of night, and also once in about eight days, to hang 



■ -Iki] 



