224 
BIBLIOGRAPHY OF ECONOMIC ENTOMOLOGY. 
1643. Riley, C. Y.—Continued. 
Chapter V: By A. S. Packard, jr. 
Permanent breeding-grounds of the Rocky Mountain locust. 131 
Permanent breeding-grounds, 131—Definition of thepermanent re¬ 
gion, 133—Its character and extent, 134—The Rocky Mountain 
locust a sub-boreal insect, 135—The sub-permanent region, 136— 
The temporary region, 13(5. 
Chapter VI: By C. Thomas and A. S. Packard, jr. 
Geographical distribution.*._«... 136 
Eastern limits of spread, 137—Northern limits, 139—Western lim¬ 
its, 140—Southern limits, 141—Sub-permanent region, 142. 
Chapter VII: By A. S. Packard, jr., and C. Thomas. 
Migrations. 143 
Classification of flights, 143—Invading swarms, 143—Returning 
swarms, 143—Local flights, 143—Height at which swarms move, 
144—Effect of change of wind and weather on flights, 145— 
Flight at night, 147—Migrations previous to 1877 east of the 
Rocky Mountain Plateau, 148—Direction of invading swarms 
prior to 1877, 149—Direction of flight in 1876, 151—Migrations 
within the permanent region, 153-158; in Montana, 153; in 
Wyoming, 156; in Colorado, 157; in Eastern Idaho and Utah, 
158; in the lower Snake Valley, 158—Return migrations from the 
temporary region previous to 1877, 159-162—Return migrations 
in 1877, 162-165—Local flights in 1877, 165—Record of flights for 
July 3 and July 20, 1877, 165-169—Summary of flights by States, 
170-174—Southward flights in 1877, 175—Movements in different 
directions at one time, 176—Destination of return swarms, 177. 
Chapter VIII: By C. V. Riley. 
Habits and natural history... 212 
Destructive powers oflocusts, 212-215—Stoppage of railroad trains, 
215— Rate at which locust swarms move, 215—Velocity of flight, 
216— Direction of invading swarms, 217—Time of appearance of 
invading swarms, 217—Flight at night, 218—Height of flight, 
219—General habits at night, 219—Where the eggs are laid, 222— 
Manner in which the eggs are laid, 223—Philosophy of the egg- 
mass, 225—The female lays more than one egg-mass, 226—Inter¬ 
val between different egg-layings, 227—Number of eggs laid, 
228—The hatching process, 228-231—Where and under what con¬ 
ditions of soil the young hatch most freely, 231—Time of hatch¬ 
ing, 231—Habits of the young or unfledged locusts in the tem¬ 
porary region, 232—Directions in which the young travel, 234— 
Rate at which the young travel, 235—They reach but a few miles 
east of where they hatch, 235 — Not led by kings and queens, 236— 
Time of year when wings are acquired, 237—Direction taken by 
swarms departing from the temporary region, 238—Destination 
of departing swarms, 238—Do the return swarms breed ? 239—Do 
return swarms from the temporary region retrace their course I 
240—The species essentially single-brooded, 240-243—Reasons 
why it cannot produce two generations annually, 243—The spe¬ 
cies can not permanently dwell in the temporary region, 244— 
The insects which hatch there do not remain, 246—Extensive and 
thick egg-laying seldom occurs twice consecutively in the same 
locality, 247—Reasons why it does not, 248—Causes of migration, 
249 -Food-plants, 251—Crops and plants most liked and those 
feast liked, 252-254—Unnecessary alarm caused by compara¬ 
tively harmless species, 255. 
