THE LOCUST OF NORTH WESTERN IXI'lA. 2455 



the information hitherto received being confined to the following: — Accord- 

 ing to a native report, dated 1890, about thirty years ago, " in the beginning of 

 spring," locusts deposited eggs in the Barkhan tahsil in Baluchistan; while with 

 regard to Persia, egg-laying was reported in September, 1889, in Shargah, and in 

 February, 1S90, in the Bahrein island. 



All the well-known locusts, hitherto studied in other parts of the world, includ- 

 ing Paohyty his migratorius of the Palsearctic zone, Caloptenus spretus of North 

 America, Stauroaotus cruciitus of Cyprus, Stauronatus inaroccannus of Northern 

 Africa, and Acridium succinctum of theDeccan, have invariably been found to pass 

 through but one generation in the year ; and this has also proved to be the case 

 with Acridium peregrinum when it occurs in Algeria. The rinding, therefore, that 

 in North-Western India, egg-laying goes on more than once in the year in the 

 same locality, has been rather a surprise to entomologists, and it has not yet been 

 definitely ascertained whether the insect really passes through more than one 

 feneration in the year, or whether the eggs found in the Autumn are only a 

 second brood laid by the insects which bad already oviposited earlier in the year. 

 The evidence hitherto obtained on the subject is somewhat scanty and contradic- 

 tory,* but on the whole tends to show that in India the insect passes through 

 more than one generation in the year, the autumn broods being the offspring of 

 the young locusts born in the spring ; and this supposition becomes still more 

 probable when it is remembered that warmth almost invariably tends to increase 

 the rapidity of insect development, and that if the same set of locusts laid both the 

 early and late batches of eggs, it is impropable that there would be any very well- 

 marked interval of time such as generally occurs, between the two periods of 

 oviposition. 



The egg-laying generally takes place shortly after slight rain has fallen : the 

 parent insects copulate, and the female forces her ovipositor for an inch or more 

 into the ground, sandy soil being usually selected for the purpose. In the hole 

 thus made, she deposits a mass of from fifty to one hundred eggs which are 

 gummed together and completely enveloped in a mass of frothy mucilage, which 

 hardens into a spongy solid that fills up the top of the hole and serves to protect 

 the eegs. The eggs take from a fortnight to three weeks to hatch, and the young 



* It is as follows : — (1) The locusts, which oviposited in Deesa in the beginning of 

 the rains of 1869, were observed by Colonel Swiuhoe to die off rapidly afterwards, so 

 that they could not have been the parents of the autumn brood of that year. (2) In 

 the Hissar district, which is very subject to invasion from Bikanir, young locnsts 

 born about July, are reported by the Naib Tahsildar of Sirsa to be said to oviposit 

 about October, when there has been rain in that month. (3) In the Rawalpind 

 division in 1890 Captain H. A. Deane observed that the locusts which oviposited in 

 August were brighter in colour, more vigorous, and, he believed, younger than those 

 which had oviposited in the previous spring. (4) On the other hand, there is the fact 

 that the locusts, observed by Dr. Ross in Rawalpindi in 1890, appeared to be as vigor- 

 ous as ever after depositing their eggs, and mi^'lit therefore have been the parents 

 of a subsequent brood. 



