STA TE A GRICULTURAL SOCIETY. 153 



themselves up by the hind legs, fold their other legs, and antennae, 

 and look very innocent and helpless for a few hours. But this is 

 preparatory to the mysterious process of molting, or shedding their 

 skins, from which they emerge twice as large and liungrier than 

 before. Six times the molting is repeated before wings are fully 

 developed. By this time the gregarious character is fully established, 

 and the strangest of movements begins. 



RETURNING SWARMS. 



No prodigal son ever strove harder to return to his father's house 

 than do these emigrants, born in distant lands, but with an instinc- 

 tive knowledge that causes them as soon as able to fill their crops, 

 assemble together, quit the country without laying eggs, and hasten 

 back as their parents came, to the home of their forefathers. These 

 returning swarms are quite different from invaders. The latter are 

 always larger, brighter colored, robust, and fierce-looking brigands. 

 The emigrants are smaller, weak constitutioned, and always more or 

 less infested with parasites. These are grubs within and lice without 

 of several sorts, that, as they feed upon their' hosts, reduce their 

 strength greatly, and eventually kill. It may be this attack from 

 parasites that drives the locust back home, but the phenomenon is 

 one of the strangest in nature. 



FIGHTING THE SCOURGE. 



As the Western settlements encroach more and more upon the 

 great plains the damage by locust invasions is relatively increased. 

 During tlie four years from 1873 to 1877, the loss is estimated at the 

 enormous sum of $200,000,000, mainly sustained by an industrious 

 farnnng_ population. The governments of the afflicted States and 

 Territories have enacted expensive legislation to combat the pest, by 

 giving one dollar to fifty cents per bushel for locusts collected and 

 destroyed, and fifty cents per gallon for eggs. Coal oil, Paris green, 

 caustic potash, and other poisons are provided cheaply and liberally 

 used. By law it is made obligatory upon all able-bodied citizens to 

 labor a certain number of days in the season in defense of the crops. 

 Twenty-two kinds of machines, more or less elaborate, are described 

 and figured in the last report of the Locust Commission. Extensive 

 systems of irrigation are instituted, cooperative action arranged for 

 protecting the prairie grass from being burned in the fall, then setting 

 it on fire in early spring to kill the young, wingless locusts. Fumi- 

 gation by burning damp straw along the borders of growing crops is 

 practiced, and effectually wards off invaders. The aid of the mili- 

 tary and Indians is invoked to assist in digging trenches for trapping 

 the young where feasible, and a signal corps of observation is sug- 

 gested to note the movements of swarms and warn threatened locali- 

 ties. In view of the immense damage stated, the economy of these 

 last measures is apparent. 



CLASSIFICATION OF LOCUSTS. 



4 



[Tho author of tliese papers aims to simplify and jiopnlarize scientific knowledge of an 

 abstruse suhject. In conversation with his neighbors — some of them hard working farmers, 

 batlling with the scourge as against the wind — an eager desire is evinced to gain correct ideas 

 of the classification, natural histor}^, enemies, etc., of the locust, hence the merely technical 



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