718 EXPERIMENT STATION RECORD. 



The results show in general that the cultural methods commonly found to 

 increase the yield of wheat have in every case increased the activity of nitri- 

 fication in soils, the different methods of experimenting giving like results in 

 this respect. It was shown in pot experiments that not only the assimilable 

 nitrogen but also the available phosphoric acid was increased by fallow and 

 by the application of manure. 



The action of carbon bisulphid and other substances on soils, K. Stormeb 

 i.T AL. {Jnhrcsher.Ver. Angew. Bot., 5 {1901). pp. H3-131 + XXXIII-XXXIX).— 

 In continuation of previous experiments the authors tested the effect on the 

 yifeld of crops grown in pots of treating the soil with carbon bisulphid, carbon 

 tetrachlorid, chloroform, benzol, toluol, xylol, phenol, o-cresol, m-eresol, p-cresol, 

 alcohol, and ether. 



All of these, except p-cresol, alcohol, and ether, decidedly increased the yield 

 of crops following fall application of the substances. Previous experiments 

 had shown that all of the substances increased the yield. An increase of yield 

 apparently occurs whether the substance used is a source of carbonaceous food 

 for soil oi-ganisnis or not, or whether the soil is " sick " or not. The authors 

 attribute the effect of the substances to their action on the nitrogen and the 

 flora and fauna of the soil. This phase of the subject was studied by tie 

 authors in water cultures and pot experiments. In the latter carbon bisulphid 

 was used at the rate of 1.6 gm. per kilogram of soil, carbon tetrachlorid 2.4 gm., 

 benzol l.G gm., xylol l.G gm., phenol 1.25 gm., and p-cresol 1.25 gm. 



The authors' results agree with those of Wagner and Pfeiffer in showing 

 that carbon bisulphid and like substances reduce denitriflcation and fixation 

 of nitrogen. Nitrification was also retarded at first, but ammonification was not 

 retarded to a like extent and later the ammonia was rapidly nitrified. 



On the influence of oxyg'en on the decomposition of vegetable matter, 

 D. Carbone and R. Marincola-Cattaneo (Arch. Fdrmarol. Spr. c Hci. Aff., 7 

 (1908), Nos. 6, pp. 265-276; 7, pp. 289-301).— From a detailed technical study 

 of the behavior of different organisms under varying culture conditions with 

 reference to the oxidation of organic matter, the authors confirm the conclu- 

 sion of Rossi that the Schizomycetes are not as a rule very active agents of 

 decomposition of organic matter. Many active agents of decomposition, how- 

 ever, are found among the Eumycetes. Oxygen seems as a rule essential to the 

 most efficient action of the organisms decomposing organic matter, although the 

 authors' results indicate that it is not possible to divide the agents of de- 

 composition strictly into aerobes and anaerobes. The authors attribute to the 

 higher fungi the more important role in the decomposition of organic matter 

 in general, and particularly cellulose, either in the absence, but especially, in 

 the presence of oxygen. They are thus important agents in the formation of 

 humus in the soil. 



Notes on the role of micro-org'anisnis in modern agriculture, especially in 

 cultivated soils, B. Heinze (Abs. in CentU. Bakt. [etc.], 2. Alt., 2l (1908), 

 No. 17-19, p. 5Jf3). — This is a review of present knowledge on various phases 

 of the subject. 



Nutrition of nitrogenous bacteria, Helene Krzemieniewska (Bui. Acad. 

 Sci. Cracovie, 1908, pp. .'I'lO-'i'i^; chs. in Jour. CJicm. Koc. [Londonli, 9'i (1908), 

 No. 550, II, p. 722). — The author's investigations point to the conclusion that 

 potassium salts are essential for the nutrition of nitrogenous bacteria notwith- 

 standing the statement of Gerlach and Vogel to the contrary. 



Inoculation experiments with Azotobacter; bacteriological studies in Madi- 

 son soil; ammonification in culture solutions as affected by soil treatment, 

 J. G. Lipman (Abs. in Centbl. Bakt. [etc.], 2. Abt., 21 (1908), No. 17-19, pp. 



