826 EXPEEIMENT STATION RECORD. 



in about the same way. In wood humus pure cultures of Bacillus denitri- 

 ficans soenieil to have a slight harmful effect, even in the second crop. 



" The growth of well-inoculated legumes did not seem to be affected in any 

 way by the presence of denitrifying bacteria. Fresh manure, whenever applied 

 to soy beans, showed an increase in yield. This increase in yield was most 

 prominent in a clay type of soil. 



"All the samples taken from different types of soil used had the power to 

 destroy nitrates when transferred to Giltay and Aberson's culture media. The 

 power of destroying nitrate was most prominent in soils to which fresh manure 

 was applied and least where well-rotted manure was applied. An increase in 

 the number of bacteria per cubic centimeter was generally followed by a 

 decrease in yield. The harmful effect of fresh manure was most apparent 

 when applied to open, sandy soils. 



" Carbon bisulphid apparently stimulates plant growth in a very active 

 manner. The use of carbon bisulphid caused an increase in yield of almost 

 100 per cent. 



" Heavy applications of fresh manure in a clay loam caused a marked falling 

 off in yield. 



" Laboratory studies show that B. denitrificans grows rapidly on almost any 

 culture medium ; on Giltay and Aberson's under aerobic conditions. It converts 

 the citrate into carbonate, thus producing an alkaline reaction. Within 14 

 days, at a temperature of 30° C, B. denitrificans will liberate virtually all of 

 the nitrate that may be present in a Giltay and Aberson's culture medium. On 

 solid media containing large amounts of nitrate B. denitrificans grows luxu- 

 riously and the gas evolved splits the agar or gelatin. This is best seen on 

 glucose formate agar. B. denitrificans forms two soluble enzyms — oxidase and 

 peroxidase." 



The loss of nitrog'sn from thin layers of manure on the soil, J. Jannes 

 (Diss. Hanover, 1910; ahs. in Zcnthl. Agr. Chem., 12 {1911), No. 8, pp. 521- 

 528). — The observations here reported were made on manure spread on soil in 

 open and closed glass dishes. 



The results in both series of experiments show that the loss of ammonia 

 depends to a large extent upon the stage of decomposition of the manure. 

 When the manure contained a large amount of ammonia the loss was quite 

 large when the manure was spread on the soil. When the manure was kept 

 moist after being spread on the soil the loss of ammonia was insignificant. 



The availability of the insoluble nitrog'sn in certain commercial fertilizers, 

 B. L. Hartwbxll and F. R. Pember (Jour. Indus, and Engin. Chem., 3 {1911), 

 No. 8, pp. 584-586). — The availability of the nitrogen of the water-insoluble 

 residue of 12 brands of commercial fertilizers was compared with that of dried 

 blood and nitrate of soda in pot experiments with a succession of oats, millet, 

 and oats. Determinations of the availabilits' of the nitrogen by the neutral 

 permanganate of potash method are also given. 



The results show that in these fertilizers, which were of high grade, the 

 availability of the water-insoluble nitrogen was practically equal to that of 

 dried blood and that the results by the potassium permanganate method agreed 

 quite closely with those of the pot experiments. 



Preliminary investig-ations on the preservation of lime nitrogen in the 

 Tropics and the changes in form, which, it underg'oes, C. J. Milo (Meded. 

 Proof stat. Java-Suilcerindus., 1911, No. 11, pp. 311-636; Arch. Sukerindus. Neder- 

 landsch-Indie, 19,(1911), No. 29, pp. 983-1035; abs. in Chem. Abs., 5 (1911), 

 No. 22, pp. 3711/, 3715). — This article reports the results of experiments during 

 1910 to determine the water-soluble nitrogen, hygroscopicity, and changes in 



