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immense numbers, wus the Dissostcira longipennis, an insect usually 

 considered rare in collections and one heretofore only known to occur 

 over the higher portions of the plains lying to the eastward of the 

 Rocky Mountains, in the States of Wyoming, Colorado, and New Mex- 

 ico. Tliis insect, as ascertained from inquiry, covered an area of about 

 400 square miles of territory in sufficient numbers to materially injure 

 the grasses growing on the ranges of the entire region, and amongst 

 these grasses the species of Bouteloua or Gramma grasses, and the 

 Bulialo grass, Buchloc dactyloides. Grains and other cultivated plants 

 did not appear to be especially attractive to it. In fact very little or 

 no injury was done by it to the cultivated crops growing within the 

 region infested. About the same time that I was investigating this 

 insect upon its northern line of injury Professors Snow and Popenoe 

 were studying it upon the southern border of its range, and they found 

 practically the same food habits there that I had noted in the north, and 

 by inquiry found that the insects had come into that country from the 

 south last fall and had laid their eggs over a large area. This year when 

 the eggs hatched the young began to move from their breeding centers 

 in all directions, seeking open places and the edges of plowed fields and 

 following roadways. This trait of seeking open spots this season is 

 probably due to the liabit of the insect of naturally living on open 

 ground, where grasses are short and scattering. The present year was 

 very wet in this particular region and caused an undergrowth of grasses ; 

 hence the desire to find the natural conditions under which the insect 

 lives. The young began moving, and, finding these open places, con- 

 gregated there. Having thus congregated, they must naturally feed, 

 and they swept the grasses clean around these spots. So noticeable 

 was this that, in certain spots where they had gathered about the hills 

 of a species of ant which raises mounds of small gravel and cuts away 

 the vegetation for some distance around them, they had enlarged these 

 areas in some places for fully half an acre. This year Messrs. Snow 

 and Popenoe observed them tlying southward with such ease, by reason 

 of their long wings, that they resembled birds. 



Dissosteira obliterata, Thomas. — Closely related to the above, and 

 very similar in ai)pearauce to it, is a second species of these large, 

 long-winged locusts, which was found in injurious numbers along with 

 Camnula pellucida in Idaho last year. It was quite common in the 

 Wood River country lying north of Shoshone and in the vicinity of 

 Boise City, Idaho. One form of this species was described by Saussure 

 as Dissosteira spurcaia in his Prodromus (Edipodorum. This is not the 

 (Edipoda obliterata of Stoll. 



Camnula pellucida. — This is the insect which has occasionally been 

 very destructive in parts of California and Nevada. It has since spread 

 eastward into Idaho, where it is very destructive the present season, 

 covering an area of at least 1,300 square miles of territory'. It also 

 appears in great numbers, with several other species, in the Red River 



