INSTITUTE, PUSA, FOR 1916-17 117 



supplemented by the adoption of methods of rearing cal- 

 culated to avoid subsequent infection, and such can only 

 be carried beyond their present imperfect stage of develop- 

 ment by making use of fuller knowledge of this subject 

 than we at present possess. I regard more complete know- 

 ledge of the life-history of Nosema bombycis and the reci- 

 procal relationships between this parasite and its host as 

 an essential preliminary to any successful solution of the 

 fundamental problem now confronting the promoters of 

 the industry. 



VI. Saltpetre. 



The artificial nitre beds described in a previous report 

 (Bulletin No. 68 of the Agricultural Research Institute, 

 Pusa), were kept under analytical observation during the 

 year; they still continue to yield saltpetre and as this is 

 remarkably free from sodium chloride, this method of 

 adding to the output of saltpetre would have the additional 

 advantage of inviting less attention from the Salt Depart- 

 ment than is usually thought necessary in the case of 

 extracts from village earth. 



A nuniah was brought in during the cold weather and 

 worked his ordinary process successfully with surface 

 scrapings from these beds. 



VII. Programme of work for 1917-18. 



Major subjects. 



1. The decomposition of organic matter in the soil by 

 bacterial action. 



2. The reciprocal relationship between bacterial activity 

 in soil and the mineral constituents of the latter with 

 special reference to phosphates. 



Special enquiries. 



3. Indigo. 



4. Pebrine. 



