INSTITUTE, PUSA, FOR 1918-19 6- 



Practically throughout the year, Mr. Howlett, Imperial 

 Pathological Entomologist, was on special duty in connec- 

 tion, firstly, with the prevention of surra-transmission by 

 Tabajiidae, more particularly among transport camels, 

 and, secondly, with the improvement of existing culicifuges 

 for military use. Reports on the work in these two direc- 

 tions have been submitted to Government. 



Problems of soil biology under investigation in the 

 Bacteriological Section during the year under review 

 were : — (1) Seasonal variations in nitrification in soils 

 under crop and fallow; (2) different rates of nitrification 

 of various organic materials in soil; (3) inhibition of nitri- 

 fication by toxins resulting from anaerobic incubation of 

 soils; (4) green-manuring; and (5) fixation of nitrogen by 

 legumes. Among enquiries of industrial value, Mr. 

 Hutchinson, besides continuing his work on indigo and the 

 pebrin disease of silkworms, succeeded during the year, in 

 collaboration with Captain Hodgkinson, in producing a 

 solution containing 3-4 per cent, available chlorine by 

 electrolysis from purely Indian raw materials, for the 

 sterilization of water. The solution can be prepared any- 

 where where electric current is available without expert 

 knowledge either of chemical or electrical methods. 



The work done by the Indigo Section is published in 

 a special series of Indigo Publications started by the 

 Institute. A separate annual report has therefore not 

 been considered necessary. 



Training. A number of post-graduate students 

 attended the Institute during the year and short courses 

 were given in sericulture and lac-culture : — 



Number of students 



General Agriculture . , ..... 2 



Agricultural Chemistry ...... 1 



Mycology ......... 2 



Economic Entomology ...... 2 



Agricultural Bacteriology (including bacteriological 



technique in silkworm disease) .... 2 



Sericulture ........ 4 



Lac-culture . ....... 2 



Total . 15 



