56 REPORT OX THE DISEASES OF SILKWORMS IN INDIA 



The examination must at all costs be careful and honest. That 

 is the great point. Whatever method is used — and the best that 

 can be afforded should be employed — every preparation should be 

 made with the greatest possible care and every examination should 

 be unimpeachable. If a fairly high percentage of pebrine, say, 

 10 per cent., is found in a lot it should be totally rejected. Efficiency 

 of examinations is a thing that cannot be too strictly insisted on. 



In these ways, by disinfection and more efficient examination, 

 the disadvantages attached to the multivoltine worms can be to 

 some extent lessened, but it must be admitted that there are these 

 disadvantages and unless the above means are taken to remove 

 them, at least in part, there will be more danger of infection in India 

 than in a temperate country, first by diseased moths not being de- 

 tected in a hurried examination and second by any infection which 

 may have been present in a rearing house in one bund not having 

 time to die out before the next comes on. 



The question of the environment of the silkworm in India is 

 peculiarly difficult. Under this heading may be included the climate, 

 the food supply, the type of rearing house and the rearer himself. 

 There is no doubt that |dl of these are of the utmost importance in 

 the study of disease. We have already seen that a hot, moist 

 climate such as one gets in Bengal for several months in the year 

 is not favourable to silkworms and is favourable to the propagation 

 of diseases. We have also seen that the bush mulberry used is 

 not so good as tree and that the amount of food given is often in- 

 sufficient. The type of house used while not so bad as some would 

 like to make out is imperfectly ventilated and lit. All these things 

 tend to make disease more easily spread and more serious in its 

 results — but we have also seen that most of these things are capable 

 of being improved quite easily. 



Here may be noted the rearing done from unexamined seed in 

 Pusa and in Berhampore Central Nursery. The seed was examined 

 in March 1921 and not again after that — the cocoons being selected 

 merely by the eye. The rearings at Pusa were done by my head- 

 rearer, a man of the peasant class, and he did all work himself 

 without any supervision. The first bund was reared in a fuhha 

 house but after that rearing was done in a hutcha house. Cages 

 infected with pebrine for experimental purposes were kept in the 

 same house, so that no special precautions were taken to prevent 

 disease except that the worms were well fed and carefully and 

 cleanly reared. Practically no disease was got in any of the lots 

 (Appendix I A and experiment 21, lots 4 and 4a). 



But here we come to the ryot himself. Any improvement will 

 have to come through him and here is the real difficulty. The 



