BIBLIOGRAPHY OF ECONOMIC ENTOMOLOGY. 219 



1625. RILEY, C. V. Continued. 

 CHAPTER II : 

 Chronological history 29 



The locust plague in the " Old World," 29 Extent of its injuries, 

 30 Migratory species in Europe, Asia, and Africa, 30 The rav- 

 ages of the locust in America, 31 Its earliest visitations, 31 In- 

 juries on the Pacific coast, 32 Injuries east of the Rocky Mount- 

 ains^ Invasions of 1818-'19, 33 Of 1845-'49, 34 Of 1855, 34 

 Of 1856, 35 Of 1857-'67, 35, 36 Of 1866, 36 Damage the follow- 

 ing year, 37 The invasion of 1873, 38 That of 1874, 39 Why so 

 disastrous, 41 General outlook in the spring of 1875, 42 Severity 

 of the injuries from the young insects that year, 43 Destitution 

 that prevailed, 44 Amount of loss sustained, 45 Destination of 

 departing swarms of 1875, 47 The invasion of 1876, 49 Eastern 

 limit reached, 53 Omaha conference, 53. 



CHAPTER III : 

 Native home and geographical range of the species east of the 



mountains 55 



Source of the devastating swarms that reach into the Mississippi 

 Valley, 55 Their origin in the extreme Northwest country lying 

 east of the mountains, 56 Cause of their emigration, 57 Differ- 

 ence between summer and fall swarms, 58 The species not at home 

 in the Mississippi Valley, 62 Not permanent or able to perpetu- 

 ate itself there, 62 Conditions which prevent such permanence, 

 63 Not likely to do serious harm east of the ninety-fourth me- 

 ridian, 65 Reasons why, 65. 



CHAPTER IV : 



Natural history and transformations 69 



How the eggs are laid, 69 Philosophy of the egg-mass, 71 The 

 female capable of laying more than one egg-mass, 72 The escape 

 of the young locust from the egg, 73 Its emergence from the 

 ground, 78 Growth and transformations, 78 Acquisition of 

 wings, 80 Number of molts, 82 Flight at night, 83. 



CHAPTER V : 



Habits and power for injury 85 



Flight and ravages, 85 Migratory instinct and great destructive 

 power confined to a single species west of the Mississippi, 88 

 Food-plants, 89 Injury to fruit trees, 93 Time of appearance of 

 invadin swarms, 94 Rate at which they spread, 95 Direction 

 of their flight, 96 Where the eggs are preferably laid, 96 Time 

 of hatching, 97 Habits of the young or unfledged locusts, 98 

 Directions in which the young travel, 100 Rate at which they 

 travel, 100 Limit of their east ward spread, 100 Not led by kings 

 or queens, 101 Direction taken by the departing swarms, 103 

 Their destination, 104. 



CHAPTER VI : 

 , Effects of the young insects in the country where they hatch, but 



where they are not indigenous 107 



Experience with the young locusts in spring, 107 Contrast in 

 summer and fall, 108 No evil without some compensating good, 

 108 Changes that follow the locusts, 109 The prevalence of 

 large green worms, 110 The sudden appearance of a peculiar 

 grass, 110. 



