62 BULLETIN NO. 4, LIVISION OF ENTOMOLOGY. 



ver and between Denver and Fort Collins. At this latter place there is, 

 as at Golden, a series of low mountains lying in front of the main range 

 and separating the open country from a series of fertile valleys and park- 

 like areas that lie back among the foot-hills and low mountains. These 

 valleys and park like openings among the foot-hills and low mountains 

 are richly clothed with nutritious grasses, and are mostly well watered, 

 thereby affording good footing for the breeding of locusts during years of 

 their presence in this section of the country, and being every year the 

 home of scores of species of " natives." It is in such localities as these 

 that the greatest variety of locusts of all sorts is to be found in Colorado. 

 What is known as the Livermore country, on the North Fork of the 

 Cache la Poudre, is a widening out of the valleys and park-like tracts 

 into quite a large area of good farming laud and a better grazing re- 

 gion. This Livermore country continues to stretch out to the west and 

 northwest until it is lost among the park-like openings on the summit 

 of the Laramie Rauge, south of Sherman ; and from here is joined to the 

 Laramie Plains on the west slope by valleys sloping that way. The 

 Laramie Plains require no description here, while the numerous small 

 parks lying to the south of the Laramie River, and between it aud 

 North Park, can be described as being merely openings in the timber, 

 varying from 7,500 to 8,500 feet above the sea, and they at times form 

 splendid retreats to the locusts and excellent grazing areas at all times 

 to cattle and the large herds of game that frequent these parts of 

 Colorado. During the summer and fall of 1880, a greater portion of 

 this country, lying between the Laramie River and the North Park, was 

 overrun by fires, during the progress of which, without any doubt, great 

 numbers of both migratory and native locusts must have perished from 

 heat and smoke. North Park is a vast grassy tract surrounded on all 

 sides by high ranges of mountains, an'd shows plainly by its leading 

 features that it was at one time the bed of a vast lake. Its lower end 

 is about 7,600 feet in altitude, while all the other portions are higher. 

 It is well watered aud grassed, thus rendering it oue of the most relia- 

 ble grazing regions in northern Colorado. While its altitude is too 

 great for safe adventure in general farming, it will nevertheless produce 

 excellent crops of vegetables and small grain. Its entire surface could 

 be burned over with some result in locust years. 



