PACKARD.! THE LOCUSTS OF THE OLD WORLD. 651 



garden-beans. The Gramihece seem to fnrnish their favoiite food. They 

 l)reter Ihe leaves and other soCt parts of plants and trees, but also some- 

 times gnaw tlie bark and even the wood of the latter. In time of 

 scarcity they will attack straw-thatch and woolen clothes, and even 

 devour each other. Koppen notices the stntement made by various 

 authors that the larva? for the first ten days live upon dew, and treats 

 it as an absurdity. 



The perfect insects copulate almost immedialely afteithe last change 

 of skin. The union of the sexes continues apparently lor a consider- 

 able time, from twelve to eighteen or even twenty Ibnr hours, but some- 

 times only for an hour or two. The female carries the male about with 

 her, and feeds as if alone ; she is, however, unable to tly. The male 

 sits quite motionless, only giving a sign ol life by stridulatiou if another 

 male should approach. 



The eggs are dei)osited about seven days after copulation. according 

 to Kostc. The lemale digs a hole in the earth of about li inches, by 

 means of the hook-like horny organs of the apex of the abdomen, and 

 the eggs are then laid in cylindrical masses, usually placed at an ang-le 

 of about 45° to the surface. The eggs are united by a spongy mass 

 (cement), which also envelopes the whole outside of the mass ; here, by 

 the adhesion of grains of sand, small stones, &c., it forms a sort of wall 

 which protects the eggs from injurious external influences. The mass 

 is sometimes formed wholly or partially of the frothy cement without 

 eggs. Yersin ascribes this to a morbid condition of the female, and 

 doubts whether the few eggs contained in such masses are capable of 

 development. Kop|)en has found, on removing the female insect, that 

 the pit which it had dug was tilled with the frothy mass without any 

 eggs. This seems to the recorder to indicate rather that the cement 

 mass is first produced by the insect, and the eggs afterward laid in it. 

 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 

 150 eggs, according to Kriinitz. The question whether the females cop- 

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

 author's statements it w^ould 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 tyx different males before laying her first batch of eggs ; and after- 

 ward the same [)henomena 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 coi)ulation 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 IGO to 170.* 



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



*In an article by V. Graber " on polygamy aud other sexual re]ationsbi])S in the Or- 

 thoptern" (Verbandlungen der zool.-botaniscber Gesellscb. in Wien, x\i, pp. 1091- 

 1(I9G, Zoological Record lor 1871), the anthor detaila experiments regarding polygan)y 

 and repeated copulations in some ortbopterous insects. A male and female were ob- 

 served in coitu eigbt distinct times between May 21 and June 1 ; after Ibe sixtb con- 

 nection 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. Analogous results followed experiments upon Pezotettix pedialris, aud be believes 

 that polygamy and polyandry exist in many species. 



