470 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



The nests found containing the spongy mass without eggs would then 

 be easily accounted for, on the supposition that the females were dis- 

 turbed or destroyed when just about commencing the actual business 

 of oviposition. The number of eggs laid in each nest seems to vary 

 from 50 to 90 or 100, and the ovary of the female contains from 100 to 

 350 eggs, according to Krunitz. The question whether the females cop- 

 ulate more than once has been much discussed in Eussia, and from the 

 author's statements it would appear that the popular opinion is that the 

 act of copulation only takes place once. From Koste's observations, 

 however, it is certain that the females copulate and deposit their eggs 

 several times. He observed a female in confinement which copulated 

 with six different males before laying her first batch of eggs ; and after- 

 ward the same phenomena were repeated four times, the insect dying 

 when engaged in oviposition for the sixth time. From his own observa- 

 tions, and those of other authors, Koppen regards, it as most probable 

 that copulation and oviposition are repeated usually at least three times 

 by each female, perhaps at intervals of about a month, as stated by 

 Yersin, the total number of eggs being from 160 to ITO.^^* 



Upon the rapidity of movement of locusts in the larval condition the 

 statements of authors are at variance. The observations of Sydon and 

 Donzingk give about a quarter of a German mile {i. e., about 0.975 mile 

 English) in the hour. Techemewsky asserts that they only advance 

 about 350 feet in the day upon grass land. 



Of the senses of the locust, Koppen se^ms to regard hearing as the 

 sharpest. The senses of smell and taste are exerted in the selection of 

 food 'j and that of touch is displayed in the sensibility of the insects to 

 changes of weather, especially temperature. Sociability is regarded by 

 the author as characteristic of the locusts. The larvae proceeding from 

 one nest seem to keep together for a time j they afterward associate in 

 larger masses which move together in search of nourishment. These 

 migrations in mass commence in the second stage of larval life, but be- 

 come more general after the second moult. The migration usually takes 

 place in the morning and evening. The author remarks upon the direc- 

 tion of the migrations of these insects, which he regards as influenced 

 to a certain extent by an instinctive perception of the direction in which 

 abundant food or a suitable breeding-place is to be found, but modified 

 or even sometimes caused by external agents, especially the winds. 

 The author also discusses the primary causes of the great migrations 

 of these insects and the phenomena observed during their flight. 



In the south of Eussia the hatching of the eggs takes place, according 

 to the weather, at the end of April or beginning of May. A few larvsB 



104 In a,n article by V. Graber " On Polygamy and Other Sexual Eelationabips in the Orthcptera'' (Ver- 

 handluDgen der zool.-botaDischeli Gesellsch. JB Wien, sxi, pp. 1091-1096, Zocloglcal liecord lor 1871), 

 the author details cxper:ments regarding polygamy and repeated ccpulationa in some orthopteroua 

 insects. A male and female were observed in coitu eight distinct times between May 21 and June 1; 

 after the sixth connectirn the female began to deposit eggs. A second male, which had already fecun- 

 dated several females, was then placed with her, and she paired at least five times with him. Analo- 

 gous results followed experiments upon Pczoteliix pedestris, and he believes that polygamy and poly- 

 andry exist in many species. 



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