196 . The Rocky Mountain Locust. 



insects, some of them having no relation to locusts, should 

 be mistaken for the Rocky Mountain pest, is natural with 

 persons who have had no acquaintance with it, and are 

 unfamiliar with its appearance. In Sept. of 1875, many 

 prominent papers of the West gave the news that the 

 dreaded swarms had finally'come into Illinois. In point 

 of fact, large swarms of locusts did pass over the central 

 portion of that State, early in September, and more par- 

 ticularly over parts of Livingston, McLean, Vermillion, 

 Ford, and Champaign counties. Small and scattered 

 flights were also seen later in the month. Some writers 

 jumped to the conclusion that said swarms were of the 

 Rocky Mountain species, without, however, giving a par- 

 ticle of proof. There is nothing absolutely impossible in 

 the occurrence of scattering swarms of the genuine spretus 

 in Illinois the year following a general invasion such as 

 we had in 1874 ; for while I have expressed the opinion 

 that the species will never do any damage east of the 94th 

 meridian, I have admitted that it may temporarily extend 

 to some distance beyond that line. But in 1875 we had 

 no reports of swarms passing over the country to the 

 Northwest or the northwest part of Illinois, prior to their 

 occurrence in the middle counties, and I felt so confident 

 that the swarms were composed of indigenous species, that 

 I so stated my belief in the Chicago Evening Journal of 

 Sept. 9th of that year, and expressed the opinion that they 

 had originated within the borders of the State ; that there 

 was no occasion for alarm, and that they would scarcely 

 be heard of after they settled. These opinions were subse- 

 quently justified by the facts ; for after taking every pains 

 to ascertain the truth, all specimens from such flights, 

 examined by competent persons, proved to be indigenous 

 species. We heard nothing of their ravages or of their 

 rising again and passing over the country to the south or 



