Waksman — xviii — Actinomycetes 



Table 29.— Antibiotic spectra of streptomycin, streptothricin, and anti- 

 biotic 136 129 



Table 30.— Numbers of bacteria and actinomycetes in the soil developing 



on albumen agar 137 



Table 31.— Distribution of actinomycetes in various soils 138 



Table 32.— Distribution of microorganisms in different soils from Bikini 



and Rongelap Islands 140 



Table 33.— Influence of 1 per cent dried blood upon the microbiological 



population of the soil 141 



Table 34.— Influence of addition of CaCO^ on the numbers of actinomy- 

 cetes in acid soils 141 



Table 35.— A list of typical actinomycetes occurring in soils and in com- 

 posts 143 



Table 36.— Influence of temperature upon the development of microorgan- 

 isms in manure composts 145 



Table 37.— Numbers of microorganisms in an undrained peat bog in 



Florida 147 



Table 38.— Decomposition of xylan by actinomycetes 150 



Table 39.— Decomposition of wheat straw by different microorganisms . 152 



Table 40.— Decomposition of sedge and reed peat by microorganisms . 152 



Table 41.— Decomposition of stable manure by pure cultures of ther- 

 mophilic microorganisms and by a mixed thermophilic population . 153 



Table 42.— Certain characters of scab-producing actinomycetes . . . 158 



Table 43.— Effect of competition of soil microorganisms upon occurrence 



of scab 168 



Table 44.— Comparative morphological and physiological properties of two 



common types of pathogenic actinomycetes 171 



Les S. chromogena et alba sont des microbes tres repandus dans 

 la terre, surtout abondants dans les racines vegetales et a leur sur- 

 face. ]e les troiivai dans le terreau de jardin jiisqii'd 1 tn. de fro- 

 fondeur; plus has encore le nomhre ahsolu de ces organismes n'est 

 guere considerable, mats depasse neanmoins celui des autres microbes 

 du sol. Cela demontre leur resistance a I'egard des conditions defa- 

 vorahles pour leur nutrition. (M. W. Beijerinck). 



