824 EXPERIMENT STATION RECORD. 



pp. 10-14). — Notiug brielly receut experiiiieuts of bis own. the author concludes 

 that from inorganic nitric compounds in sunshine in the presence of formalde- 

 hyde more complex nitrogen compounds are formed, this fact furnishing on the 

 chemical side support for the view that assimilation of nitrates and nitrites 

 is a photochemical process. 



Contributions regarding the effect of manganese and aluminum on plant 

 development, II, T. Tfeiffer and E. Blanck (Landw. Vos. iStat., 83 {1913), 

 2^0. 3-Jf, pp. 257-281) .—The authors, reporting further studies (E. S. R., 28, 

 p. 328) state that manganese salts but slightly increased the production of 

 dry substance in small grains, but that the organic substance was considerably 

 increased. Aluminum sulphate in small quantities with small proportions of 

 manganese sulphate showed only a slight stimulation of yield, while the addi- 

 tion of aluminum rapidly decreased the returns, exceeding manganese in this 

 respect. These investigations are said not to have borne out the claim of 

 Stoklasa (E. S. R., 25, p. 522) regarding the neutralization by aluminum of 

 the injurious effects of the manganese salt. 



Influence of metals on development of Aspergillus niger in Raulin^s 

 liquid, M. Bornand (Centbl. Bakt. [etc.}, 2. AM., 39 {1913), No. 18-19, pp. 

 488-496, figs. 4). — ^It is stated, as a result of a study of A. niger in Raulin's 

 fluid in contact with metallic platinum, aluminum, silver, copper, iron, tin, 

 lead, zinc, and nickel, that the growth of this fungus is rather hindered than 

 promoted by the presence of all but the first two, and that normal development 

 is not shown after the substitution of iron and zinc for their salts used in 

 Raulin's fluid. 



A contribution to the theory of antagonism, W. J. V. Osterhout {Ahs. in 

 Science, n. ser., 39 {1914), No. 999, p. 292). — It is claimed that by means of 

 electrical measurements of living tissues it is possible to predict which salts 

 will antagonize each other when allowed to act upon these tissues. 



The effect of antagonistic or balanced solutions containing sodium chlorid 

 together with one of the chlorids of calcium, magnesium, potassium, 

 strontium, ammonium, or copper, upon the growth of com plants rooted 

 in an artificial soil, J. S. Caldwell (A'bs. in Science, n. scr., 39 {1914), No. 

 999, p. 293). — A preliminary account is given of experiments carried on with 

 each of the 6 pairs of salts to determine their effect on plants growTi in finely 

 divided quartz. For each pair of salts 10 to 20 different concentrations were 

 used, varj'ing from the lowest concentration that inhibited development to a 

 dilution so great as to be without effect upon the plants. In all cases results 

 were measured by comparing the dry weights of the roots and tops taken sep- 

 arately, the cultures being allowed to grow under controlled conditions for 30 

 days. 



Antagonism was observed between sodium and strontium at all molecular 

 ratios between 10 : 1 and 20 : 1, and in all concentrations between those just 

 permitting measurable development and those too dilute to have any discover- 

 able effect, except that of root development. The effect of the additions of cal- 

 cium to sodium was merely to decrease the characteristic physiological and 

 moi-phological effects of sodium in a degree directly proportional to the amount 

 added, the effect being one of dilution and not of antagonism. 



In mixtures with copper, sodium, served merely to dilute the copper salt, 

 decreasing the toxic or stimulatory effect directly proportional to the amount 

 added, but in no case annulling the effects of the copper^on. 



Additions of magnesium to sodium in any proportions or at any concentra- 

 tions were without effect upon the development of the aerial parts. In highly 

 toxic concentrations mixtures in the ratio of 2 : 1 gave somewhat better de- 

 velopment of roots, while in all stimulatory concentrations of 1 : 1 gave the best 



