SOILS — FERTILIZERS. 6 1 7 



in the Colorado soils, and in some places to an appreciable extent." they do 

 maintain " that whatever theory is nsed to account for the accumulation of 

 chlorids in the Colorado soils will also account for the greater portion of the 

 nitrates present." 



Ammonia and nitrate assimilation by micro-organisms of the soil, J. 

 YoGEL {Centhl. Bakt. [etc.], 2. Abt., 32 {1912), No. 6-12, pp. 169-179; abs. m 

 Jour. Soc. Chem. Indus., 31 (1912), No. J,, pp. 195, 196).— The experiments 

 with culture solutions and with natural soils here reported led to the conclu- 

 sion that while there is an appreciable formation of albuminoid matter from 

 ammonia and nitrate in culture sojutions there is no such fixation of nitrogen 

 in natural soil, and that the fixation of ammoniacal nitrogen is promoted by 

 the addition of calcium carbonate in culture solutions but not in the case of 

 natural soils. When calcium carbonate was present in soils containing am- 

 monia salts there was considerably greater loss of nitrogen than could be 

 entirely accounted for by the volatilization of the ammonia, and the author 

 is of the opinion that under the conditions prevailing in these experiments, 

 involving imperfect aeration, there was a loss of nitrogen due to denitrification. 



Inoculation experiments with Azotogen, M. Popp (Dent. Lfindw. Pressr, 

 38 (1911), No. J,2, pp. .',!I2, J,9.] ; ahs. in Centhl. Bald, [etc.], 2. Abt., 32 (1912), 

 No. 6-12, p. 269). — Comparative tests on horse beans of (1) seed inoculation 

 with gelatin cultures, (2) seed inoculation with soil cultures, and (3) soil inocu- 

 lation with soil cultures, made on upland moor soil which had never grown 

 horse beans, showed decided benefit from inoculation in all cases, but especially 

 fi'om seed inoculation. 



The direct assimilation of inorganic and organic forms of nitrogen by 

 higher plants, II. P>. Hutchinson and X. H. J. Miller (Jour. Agr, Sci., Jf 

 (1912), No. 3, pp. 282-302, pi. 1; abs. in Jour. Hoc. Chcm. Indus., 31 (1912), No. 

 Jf, p. 195). — This is a somewhat more detailed account of investigations of 

 which a brief report has already been noted (E. S. R., 26, p. 32). 



It is stated that the results which were obtained in water cultures with 

 peas are not yet sufficiently numerous to make it possible to trace any connec- 

 tion between the assimilability and the composition of the nitrogenous com- 

 pounds. In the experiments reported the best results were obtained with urea 

 and barbituric acid if humus, which is of indefinite chemical composition, is 

 excluded. Next in ox'der were acetamid, ammonium sulphate (without calcium 

 carbonate), formamid, alloxan, glycin, alanin, peptone, oxamid, guanidin, and 

 cyanuric acid. 



Leguminosas and Gramineae grown separately and in mixture, with especial 

 reference to utilization of nitrogen, F. Pilz (Ztschr. Landw. Versuchsw, 

 Osterr., 1!^ (1911), No. 10, pp. 1150-1210; abs. in Intemat. Inst. Agr. [Rome], 

 Bui. Bur. Agr. Intel, and Plant Diseases, 2 (1911), No. 11-12, pp. 248i-2'/86).— 

 Peas and barley and oats and vetch were grown separately and combined, as 

 indicated, in pot exi>eriments, and these and corn and horse beans were grown 

 in field experiments with and without applications of fertilizers. 



The results obtained show that the yield of diy matter per unit of area 

 was greater for the mixtures than the sum of yields of the crops grown sepa- 

 rately, but was smaller as compared with the amount of seed used. The yield 

 of dry matter was affected less by fertilizers in the case of mixtures than in 

 the case of the separate crops. Leguminous plants grown in the mixtures were 

 poorer while cereals were richer in nitrogen than in case of the crops grown 

 separately. There was an increase in the nitrogen content of the leguminous 

 crops only when these made poor growth and the soil contained a sufficient 

 amount of nitrates. The increased nitrogen content of cereals grown with 

 leguminous plants is attributed to the diminished gi'owth of the cereals and 



