812 mOCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 



fluid only from the colon for microscopical examination, tlie examiner 

 must be found fault with and not the system. 



Mr. Hutchinson's 5_ Recently another modified method of Pasteur has been recom- 



method. mended to be practised in India and elsewhere {vide Bulletin No, 75, 



the Pebrine disease of silkworms in India, by Mr. C. M. Hutchinson, 

 Imperial Agricultural Bacteriologist, Agricultural Research Institute, 

 Pusa). In this method " a minute portion of the gut, removed on the 

 needle and rubbed with water on the slide," is examined under the 

 microscope. If it contains pebrine spores the eggs laid by the moth 

 are destroyed but if no pebrine Spores are seen the eggs are kept for 

 reproductive purposes. This modified method is said to be Superior to 

 all other existing methods. I have made a comparative Study of this 

 modified method and the Pasteur method. The number of pebrinized 

 and healthy mother-moths as observed by me are enumerated in the 

 Tables on next page. The eggs of these consignments were from diseased 

 stocks. 



Thus out of 598 moths examined according to the Pasteur method 

 I found 459 pebrinized moths and 139 healthy ones and out of the same 

 number examined according to the modified method of Pasteur as advised 

 by Mr. Hutchinson, I found 455 pebrinized moths and 143 healthy ones. 

 The latter method takes a longer time than the former but does not 

 appear to be more effective. It should be noted in this connection that 

 one examiner can examine the following number of moths in different 

 countries in one day of eight hours : — 



Pasteur method — 



France 1,000-1,200 



( Vide Manud Pratique du Sericulture by Alp. Blanchan. 

 Number of working hours per day has not been men- 

 tioned ) 



Japan 700-900 



Kashmir . . 700-900 



Mysore 600 



Mukerji's method — 



Bengal ' . . . 250-300 



Hutchinson's method — 



Pusa 200-250 



Vide Proceedings of the 37th Regultir Meeting of the 

 Bengal Silk Committee held in Calcutta on 5th July 

 1918. 



I examined 300 moths in 8 hours according to the last method. 



