446 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



All these reports, as we were able to prove by examiniug specimens, 

 had reference either to the Eed-legged (femur-ruhrum) or the Lesser 

 (atlanis) locust, and in no Instance was a specimen of theWestern spretus 

 among them. 



In 1875 the State of Illinois was visited by migrating locusts which 

 passed over the central portion of the State, particularly parts of Liv- 

 ingston, McLean, Yermillion, Ford, and Champaign Counties. These 

 flights occurred early in September, though smaller, scattered flights 

 were noticed later in the month. As usual, in this case they were pro- 

 nounced to be spretus by many writers, who jumped at the conclusion 

 without the slightest possible proof. Prominent journals also pub- 

 lished the intelligence that the Eocky Mountain locust had actually 

 crossed the Mississippi. 



We did not hesitate at the time to announce that the reference of 

 these swarms to the Eocky Mountain locust was an error, and that they 

 consisted of species native to Illinois. The correctness of these opinions 

 was proved by subsequent facts, as the species examined in every case 

 were found to be indigenous. Their flights were irregular and poorly 

 sustained, and nothing washeard of their ravages or of their again taking 

 flight. 



On September 15th of that year we received from Mr. H. P. Beach, 

 county judge of Ford County, Illinois, the following letter, inclosing 

 specimens: 



About ten days ago myriads of grasshoppers flew southward over town. Many of 

 them came down, evidently unable to keep up the journey. They seemed to be all the 

 way from a hundred feet to a quarter or half a mile high, or perhaps very much higher. 

 In looking up toward the sun, the only way they could be seen, the appearance was 

 much like that of a snow-storm looked at in the same way. We have not heard from 

 them since, and of course can give you no idea whence they come or whither they go. 



About the same date (September 16), Mr. B. F. Johnson, Champaign, 

 111., correspondent of the Country Gentleman, supposing the species to 

 be spretus J wrote to that journal as follows : 



When first seen, their movements and motions were so unlike what I had conceived 

 their flights to be, that it was not till several disabled or partially exhausted insects 

 had been caught, and their identity with the Kansas species demonstrated, that I was 

 convinced of their true character. I had supposed that these creatures flew in a man- 

 ner as pigeons and ducks and geese do — straight ahead in a given direction, and with 

 a purpose. On the contrary, every insect seemed to be out on a holiday, and acting 

 independently of all the others. While the vast mass slowly moved south, with an 

 inclination toward the east, there was a constant circular movement of a vast 

 majority of the whole number of individuals. ***** 



When it got noised abroad that they were flying, the fact produced a startling sensa- 

 tion. Would they increase in numbers till the sun was darkened, and then descend 

 and devour up every green thing, and leave eggs for a progeny behind them that 

 would repeat the disaster next summer ? These fears were speedily dispelled when 

 their numbers were seen to diminish, and when it was considered that all the grass- 

 hoppers which had passed over, did they come down could make but small impression 

 on the ten thousand square miles of corn in Central Illinois. 



