112 Indian Museum Notes. [Vol. IL 



ens into a case for the eg-gs. The eggs have been found to withstand 

 as low a temperature as 26° F. below zero. The dry steppes constitute 

 the chief haunts of the locusts, which avoid damp places. The females 

 generally oviposit in solid virgin soil, and seldom visit ploughed land for 

 this purpose. Koppen is of opinion that the countries in which the 

 swarms are seen are also, generally speaking, the countries of their 

 origin, 



Pachytylus cinerascens, Fabr., and (Edipoda tatarica, Motsch., which 

 have been described by different authors as distinct from P. migraforius, 

 are considered by Koppen to be but varieties of one and the same species 

 (Horse, Soc. Ent. Ross, iii, 1867). P. cinerascens is the form which has 

 usually appeared in England and Belgium, in the latter of which coun- 

 tries Koppen notices that it probably breeds (Zool. Record, 187S, p. 398). 

 It also occurs in India 'vide pp. 101 to 104 on Locusts in Madras). 



PacTiytylu8 pardahnus has been described as destructive in South 

 Africa (Trans. Soc. Afr. Phil. Soc. i, p. 193, 1880). 



Pacliytylus stridulus^ (Edipoda vastator, Stauronotus vastator, and 

 Pezotettix alpina have been noticed amongst other locusts as occasionally 

 destructive in Southern Russia, especially when associated with the com- 

 mon migratory species Pacliytylus migratorius and Caloptintis italicus 

 of that region (Koppen, Horse, Soc. Ent. Ross, iii, 1867). 



Caloptftnus spretus, the Rocky Mountain locust (see Reports of United 

 States Entomologists-— Riley, Pachard and Thomas,- — Washington, 1877- 

 79), caused injury, between the years 1874 and 1877, estimated at 200 

 million dollars. It breeds permanently only in a broad and compara- 

 tively barren region in the north-west of America, whence the invading 

 winged swarms swoop down upon the fertile plains of the south and south- 

 east, not appearing in the Mississipi valley until the latter part of 

 July or the beginning of August, when wheat, barley and oats have 

 generally reached perfection and been harvested. This, it is reported, 

 retiders it possible to prevent serious injury by relying chiefly on these 

 crops when there is reason to fear incursions. On arrival the locusts 

 devour everything green to be found, until they deposit their eggs and 

 die in the autumn. From these eggs are produced in the spring vast 

 hordes of young which devour everything green they can find, travelling 

 along the ground (not having yet acquired wings) from the fields they 

 have exhausted to fresh ground. They may be destroyed in vast numbers 

 by systematic rolling, collecting by hand, by drawing bags over the field, 

 &c., and their advance may be prevented by digging ditches in front of 

 them with a streak of tar at the bottom, and also by driving them into 

 heaps of straw to be then burnt, the trees being protected by bands 

 formed of poisonous or impenetrable substances. When the larvoe are 

 full-fed and acquire wings they rise up, by this time followed by hosts 



