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Rocky Mountain Locust deposits its eggs, is a different question. 

 The same species has laid eggs in Kansas, this year, as late as the 

 13th of November, and may continue to lay in Texas as late as 

 the first of December. (Riley's 7th Ann. Report, p. 192.) If the 

 mission of the locust is to lay eggs once and die, what could be 

 the time or place of birth of those insects which have apparently 

 first reached maturity by the first of December ? Although it has 

 been considered possible that these are a second brood whose pa- 

 rents were hatched in the preceding April or May in Texas or Col- 

 orado, there is no knowledge of the time or place of any such sec- 

 ond hatching. If these late laying swarms are such as those which 

 come down from the Snowy Range in Colorado, in the latter part 

 of August (vide N. C. Meeker, quoted in Riley's 8th Ann. Report, 

 p. 84) it must be admitted that the mountain-born broods are a 

 longer- lived and more vigorous race than any bred in Minnesota. 

 Besides this, among the swarms which have come in upon us this 

 year, many were found dying as late as October, containing eggs. 

 That the Rocky Mountain Locust lays eggs twice or three times in 

 a lifetime, has been the result of some guess-work among our far- 

 mers, who considered it necessary in order to account for facts as 

 they saw them. I give the result of a single experiment. 



On the 25th of June, I shut up in wire gauze cages nine pupa) 

 of the Rocky Mountain Locust. The bottoms of the cages were 

 filled with earth packed hard, and the insects appeared to thrive in 

 confinement. By the second of July they had all become perfect 

 insects. By the 8th of July they commenced coupling, and were 

 seen repeating the act for several days. On the 15th and 16th two 

 of the females went through the form of depositing eggs, and I 

 marked the place of deposit on the edge of the cage. The coupling 

 was repeated again as before, until the third of August. At that 

 date the coupling ended, and the locusts became almost inactive, 

 and were seen to eat very rarely afterward.* 



On the 14th of August one of the males died ; the female died on 

 the 9th of September, and was found to contain fourteen full 

 sized eggs, but I found on examining the cage that there was also 



* The early part of this coupling season was one of the greatest activity 

 on the part of these insects; they dashed themselves against the wire of 

 their cages as though all space would be too small to contain them; there 

 would be a flash of the wings, extended and closed again in an instant, or 

 that movement of the hind legs known as " flddliDg," which seemed to be a 

 well known signal between the male and female. In cages, where several 

 pairs were confined together, the male, while in the act of coupling, would 

 repeat this movement, if brushed against by another. 



