63 



the nio-ht and thaw out next day to renevr o])erations. Sometimes 

 they are buried in the snow and remain buried without apparent 

 inconvenience until that is uieUed. 



Hayden is situated on the Bear River north of the "Williams River 

 Mountains. Two visitations are recorded at this place. A brood 

 came through in 1882, at vrhich time there were l>ut few settlers in the 

 valley. These i)rotectet! their crops in part by herding. The second 

 invasion was during the present year, and proved to be much more 

 severe than the first. It evidently came from the Williams River 

 Mountains and appeared at the town about the 1st of June. The 

 insects traveled east and stopped at nothiug in their course. In the 

 town they climbed over the board fences and houses with the greatest 

 ease. They entered open doors and made themselves at home by the 

 family fireside. On reaching a ditch they leaped in and many were 

 drowned. The dead and the living which did not succeed in reaching 

 the opposite bank floated on the water, and, lodging against a dam, 

 formed a pile a foot deep, 30 feet long, and 4 feet wide. The brood 

 proceeded on its way until it came to the Bear River, where it Avas 

 deflected to the north, and, folloA^ing the course of the river, came 

 about and visited the people of Hayden again a few weeks later. 

 After this they retired to the dry hills 3 or 4 miles south of town, 

 where they were to be found at the time of our visit in the latter part 

 of July laying eggs. A diligent search for eggs failed to disclose 

 them in any considerable numbers. 



The most remarkable record was made at Lay, a town nearly west 

 of Hayden and 7 miles north of the Bear River. A brood passed 

 through here in 1805. It came from the southwest and went to the 

 north. It was not a very large one and was never heard from after- 

 ward. This is the onh^ verified instance of the insect having crossed 

 Bear River. The swarm, before it reached the river, must have been 

 enormous, for even the great numbers at Hayden this year faileil to 

 effect a passage. 



A glance at the map (fig. f^) will show that the number of migrations 

 recorded and the directions traveled support the testimony given by 

 difierent individuals that Anahri(f<- simplex is permanently located 

 in the Danforth Hills. From this center migrations of insects 

 occur nearly every year. The number of individuals in each band 

 varies greatly and determines, in a large measure, the distance from 

 the home ground that it will ultimately travel before becoming 

 extinct. 



The paths of three great migrations are fairly well made out. 



A band passed througli Hamilton in 1879 and proceeded to the 

 Williams River Mountains, Adhere the}^ became established. Three 



