63 
the night and thaw out next day to renew operations. Sometimes 
they are buried in the snow and remain buried without apparent 
inconvenience until that is melted. 
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 which time there were but few settlers in the 
valley. These. protected 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 nothing 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 was 
deflected to the north, and, following 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 1895, 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 only 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 failed to 
effect a passage. | 
A glance atthe map (fig. 6) will show that the number of migrations 
recorded and the directions traveled support the testimony given by 
different individuals that Anabrus simplea 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 through Hamilton in 1879 and proceeded to the 
Williams River Mountains, where they became established. Three 
