INDEX 



Acidity in soil, determination of , 151 

 Actinomycetes, agar for, 122 



solution for, 122 

 Agar for preserving plates, 1 26 

 nutrient, 92 



to clear, 93 

 washed, 105 

 Alcohol for denitrifying solution, 107 

 Alfalfa plant with nodules, 70 



with and without bacteria, 71 

 Algse, solution for, 123 

 Ammonia, determination of, distilla- 

 tion, 141, 142 

 Nesslerization, 142, 143 

 Ammonification by pure cultures, 46 

 effect of depth on rate, 42 

 of limestone on rate, 44 

 of moisture on rate, 43 

 of potassium phosphate on rate, 



45 

 of soil type on rate, 41 

 of blood-meal, 39 

 of casein, 39 

 of clover hay, 39 

 of gelatin, 38 

 of urea, 35, 36 

 Ammonifiers, isolation of, 39 

 Ammonium sulphate, nitrification of, 



Sx 

 Anaerobic jar, 133 

 nitrogen fixation, 66 

 fixing organisms, isolation of, 66 

 Aniline oil gentian- violet, 128 



Apparatus for determining catalytic 

 power of soils, $3 



for one student, 11 

 Artificial cultures for inoculation of 



legumes, 73 

 Ashby's solution, 108 

 Asparagin-dextrose agar, 95 

 Atomic weights, 164 

 Azotobacter, formation of pigment, 



influence of various culture-media 



on growth, 65 

 isolation of, 61 

 nitrogen fbcation by pure culture 



of, 64 

 relation to oxygen, 65 

 stained with methylene-blue, 62 



Bacillus coli, 57 

 Hartlebii, 57 

 pyocyaneus, 57 



radicicola, effect of, on growth and 

 nitrogen content of alfalfa, 71, 

 72 

 from alfalfa, 68 

 from clover, 67 

 gum formation, 7$ 

 isolation from different legumes, 



67 

 nitrogen fixation j in solution, 72 

 radiobacter, 62 

 subtilis, 46 

 tumescens, 46 



165 



