1914] Liptnan-Burgess : Ammonification in Smls by Pure Cultures 153 



organisms mostly identical with those in Series I seem to mani- 

 fest a distinctly high efficiency which the much larger number 

 of the balance do not in most cases even approach. It is worthy 

 of remark, moreover, that B. mycoides attains or rather ap- 

 proaches in portions of Series II its position of prime importance 

 which has thus far so generally been accorded it among ammoni- 

 fying organisms. 



Series III. Cottonseed Meal 



The cottonseed meal used in this series showed on analysis a 

 nitrogen content equal to 5.5 per cent. The experiment in this 

 series was otherwise conducted like those of Series I and II, 

 2 per cent of cottonseed meal being used, or 1 gram per 50 grams 

 of soil. The results are shown in Table III. 



Again the efficiency of the organisms tested is much greater 

 in the sandy soil than in either the clay-loam or adobe soils. 



Sandy Soil 



In this part of Series III the organism of greatest ammonify- 

 ing efficiency is B. tuniescens. Those approaching it closely in 

 efficiency are B. vidgatns, Sarcina lutea, and B. mycoides in the 

 order named. B. ramosus takes fifth place and the next three 

 organisms fall more than 33% per cent short of producing the 

 amount of ammonia yielded by B. tumescens. They are B. 

 mesentericus, B. megatherium, and B. proteus indgaris. The 

 balance of the organisms show only about half the efficiency of 

 B. tumescens and in one case, B. icteroides, which has in all pre- 

 vious series vshown a very low efficiency, only about 25 per cent 

 of the maximum efficiency is manifested. Taken as a whole, the 

 data given in Table III for the Anaheim sandy soil reflects 

 favorably on cottonseed meal as a source of available nitrogen 

 under the conditions named. Again, the greatest efficiency is 

 manifested in this section of Series III by organisms which in all 

 cases have shown high efficiency in other series above reported. 

 As in the case of the heavy soil in the preceding series with 

 tankage, B. mycoides also shows marked efficiency in the light soil 

 when cottonseed meal is used. 



