86 Indian Economic Entomology . [ Y6L L 



of the fly, after depositing its own eggs, may thus be comprised within 

 about twenty-eight days, made up as follows :— 



1 day passed in the egg. 



7 days „ as a maggot. 

 12 days „ as a pupa. 



8 days the supposed life of the fly. 



Total . 28 



These periods, however, vary with temperature and other conditions, 

 for maggots have beeu known to become pupae as early as the fourth day 

 of their existence, and to produce small flies : while Cleghorn believes 

 that a large number of pupae hybernate from November to February. 



According to Louis the flies bred from the Rains bund emerge so 



„ ,. long before there are any worms of the Novem- 



Rcmedies 



ber bund, upon which to oviposit, that they die 



without producing offspring, and hence at this time of the year the 

 pest almost completely disappears. Reproduction, however, is so rapid 

 amongst the few individuals which do manage to survive that by the 

 following Rains bund, or even by the end of the March bund, there 

 are sufficient flies to occasion much injury. Louis recommends that a 

 persistent effort should be made in silk factories, in the early part of 

 each year, to destroy the pupae of the fly. At present little is done, 

 except by keeping the rearing-houses in almost total darkness, and 

 closed in with thick purdahs ; aud this purely defensive attitude, he 

 considers, is insufficient to keep out the fly, while it deprives the worms 

 of much of the light and air they require. 



Mukerji notices that flies are specially injurious in the August- 

 September bund, which is not one of the principal bunds, rearing being 

 only done by those who have leaf left after the immediately preceding 

 July bund. The reason why this bund is specially injured is, he 

 believes, because the flies, which have emerged from the worms of the 

 July bund, appear just in time to oviposit in the worms of the August- 

 September bund. He, therefore, suggests that the practice of withhold- 

 ing rearing every alternate bund in the same neighbourhood, should be 

 made compulsory through the agency of village panchaiats. This practice, 

 being already very generally followed, the loss of the silk that is reared 

 between the July and November bunds would not be considerable. 

 If this action were taken, he thinks that the only remaining source of 

 flies would be the seed cocoons, which could be obtained free of fly by 

 rearing them under wire netting in properly managed central estab- 

 lishments. With regard to the advisability, however, of making 

 regulations which must necessarily occasion at least temporary loss to 

 those who now find, in spite of the fly, that it pays to raise an Autumn- 

 September bund, the writer would suggest that investigations should 



