31 
forward sliding thrusts, with an occasional side movement. In this 
manner the hole thus formed becomes a little elongate in form and 
somewhat larger at the lower end than above, making as enlarged 
cavity for the reception of the eggs, which arc irregularly arranged. 
These eggs are somewhat curved, of dark brown color, of an average 
size for the insect which lays them, being nearly one-third of an inch in 
length and are somewhat flattened, but otherwise do not differ much in 
form from those of an ordinary grasshopper, or Locust as they should Im- 
properly called. They are not all laid at one time, but, judging from 
dissections made of the female, 15 to 18 are laid in one cluster, other 
deposits following at intervals of several days during the fall. Last 
summer they began laying about the middle of July and continued 
during the first week in September. It was not definitely settled as 
to the arrangement and number of eggs laid in a single cavity, but the 
figures given above can be taken as approximately correct. 
A second, but much smaller, species of these crickets also occurred 
in numbers near and among the foothills of the mountains adjoining the 
prairie. This latter species is evidently the one described by Prof. ( Jy- 
rus Thomas as Decticus triUneatus, though from its great variability in 
coloration and markings it is quite difficult to decide this for a certain ty 
without careful comparisons of a number of specimens with the descrip- 
tion. Contrary to the clumsy movements of the large Anabrus simplex, 
this smaller cricket is one of the most active insects in the region, and 
to capture a specimen of it during the warmer part of the day requires 
considerable dexterity on the part of the would-be captor. Its egg- 
laying habits were not ascertained since it apparently had not yet be- 
gun operations in this direction. 
Some apprehension is felt by many of the inhabitants that this latter 
insect will also become injurious, since it was noticed for the first time 
the present year in such numbers as to cause alarm. I do not think 
that such is liable to be the case, since it appears to be partial to damp 
places covered with rank vegetation rather than to the more dry open 
country. It occurred in the mountains at an altitude of 9,000 feet above 
sea level or near timber line, as well as down in the valley below the 
5,000 feet point. 
The migratory habit in Anabrus simplex and several others of these 
large, wingless, cricket-like insects is veiy marked at times; but much 
more so when they are present in large numbers. As with many 
other insects when they develop in excessive numbers, the desire to 
move in great crowds seems to take hold of these crickets. At such 
times they move towards central points and congregate into companies, 
after which they strike out in a body in some particular direction. 
When moving they are said to turn neither to the right nor to the Left, 
but to keep on in a direct line 1 , climbing over obstacles rather than going 
around, and even plunging into streams which happen to run across 
their course of travel. When these streams are encountered, it" not too 
