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This invasion is known to be due to C. devastator, which outnumbered all other spe- 
cies combined in proportion of 7 to 1. The next in abundance was the ash- 
colored locust, which was only one-twentieth as numerous as the former. 
Mr. Coijuillett's account of this year's invasion is to bo found in Annual 
Department Report for 1885. Mr. Koebele also gives an account in the same 
report on the locusts about Folsom, California, in 1585, the greater part of 
which belonged to this species. 
Life-history and Habits. — The habits of this locust are much the 
same as those of the precediug species. We have few exact data ou this 
poiut. The locusts have beeu fouud mature aud iu force early iu Juue. 
They are generally much more abundant in the foothills along the sides 
of valleys, and it is probable that these are their usual breeding places. 
It seemed evident from the 1885 investigations that the locusts did not 
migrate from a distance, but bred in the vicinity of the plantations : 
for while the edges of these during the first part of the invasion were 
well stocked with locusts, there were only a few in the center. Young 
locusts which were referred to this species were found in some num- 
bers upon uncultivated lands bordering plantations. These waste 
places are covered with water during the winter, and sometimes until 
late in summer. When seeding time arrives, they are too wet to be 
plowed and seeded and thus remain undisturbed. The green vegeta- 
tion of these waste places furnishes food to the locusts late in the sea- 
son, when other fields are bare, until the egg-laying season arrives. 
The subsequent submersion through winter does not seem to affect the 
vitality of the eggs. 
THE DIFFERENTIAL LOCUST. 
(Galoptenus differentialis Thos.) 
Range of the Species. — This locust ranges through Illinois, Mis- 
souri, Nebraska, Kansas, and Iowa, It is also found in Indiana, Texas, 
Xew Mexico, and California. 
Destructive Appearances.— This and the following species are 
much larger than the preceding ones, and though like C.femur-rubrum 
they do not possess the migratory habit, they can and occasionally do 
Fig. 8. — Oaloptenus differentialis, natural size (after Riley.) 
make considerable flights. We have devoted some space in the first 
report of the commission to accounts of damage by this species. It was 
abundant in 1875 in central Illinois and attracted considerable atten- 
tion. It was accompanied by the Red-legged and Lesser Migratory 
