AGRICULTURAL CHEMISTRY AGROTECHNY. 803 



Some observations on phytin, W. Heubner {Biochem. Ztschr., 64 (1914), 

 No. 4^-6, pp. 409-421) .—The author finds that phytic acid is only gradually 

 cleaved in a 1.5 normal acid solution at 37" C. Less than 1 per cent of the 

 amount present is cleaved per day. Light accelerated the cleavage through 

 acid very much. 



The hydrolysis of maltose by hydrochloric acid under the Herzfeld con- 

 ditions of inversion. A reply to A. J. Kluyver, W. A. Davis (Joxir. Agr. Sci. 

 [England}, 6 (1914), No. 4, pp. 413-416) .—" It is shown that contrary to the 

 statements of Kluyver and otliors, maltose undergoes slight hydrolysis (to the 

 extent of about 2 per cent when 1 per cent solutions of maltose are used) 

 when heated with hydrochloric acid under Herzfeld conditions. It is prefer- 

 able, therefore, to adopt 10 per cent citric acid, under the conditions formerly 

 laid down, in estimating cane sugar in plant extracts when maltose is likely 

 to be present." 



The influence of low temperatures on enzyms, J. S. Hepburn (Biochem. 

 Bui., 4 (1915), No. 13, pp. 136-150).— A review. 



Habituation of lactic ferments to poisons, C. Richet (Rev. G4n. Bot., 25 

 bis (1914), pp. 583-587). — The lactic ferment is found able to accustom itself 

 progressively (as shown by increased acid formation) to solutions of potassium 

 bromid. The optimum of adaptation was obtained at relatively high concentra- 

 tions of the toxic salt, but if returned to the nonpoisonous mixture it recovered 

 its normal powers in one or two days. 



The significance of the amount of low molecular glycerids of fatty acids 

 in milk fat of various animals, E. Gutzeit (Kiihn. Arch., 5 (1914), pp. 127-^ 

 138). — The Reichert-Meissl number of woman's milk fat was found to be 2.03. 

 This is in agreement with the findings of Laves (2.5) and Pizi (1.42), but not 

 with Sauvaitre (15.8). The Reichert-Meissl mtmber of the fat in cow's, sheep's, 

 and goat's milk is two or two and one-half times greater than the fat in asses' 

 and mare's milk, and in the latter the Reichert-Meissl number is six times as 

 great as in human milk. Pig's and dog's milk contains still less of these volatile 

 fatty acids. Accordingly, it is concluded that herbivorous animals require milk 

 with fat which contains a high water-soluble volatile fatty acid content and 

 the omniverous and carnivorous animals a milk fat with a low one. 



The relation of the excessive amount of fatty acids of cow's milk fat to in- 

 fantile gastrointestinal disorders is discussed. 



The estimation of inorganic phosphoric acid in the presence of phosphoric 

 acid esters, W. Hextbner (Biochem. Ztschr., 64 (1914), No. 4-^, PP- 401-408). — 

 Inorganic phosphoric acid in the presence of 4 per cent by volume of concen- 

 trated sulphuric acid and 15 per cent of ammonium nitrate can be precipitated 

 quantitatively at a temperature of 37° C. within 6 hours as ammonium phospho- 

 molybdate. The presence of small quantities of phytin does not influence the 

 results, but increasing amounts of this substance do. Glycero-phosphoric acid 

 affects the results much less than phytin. 



About the calculation factor used in determining phosphorus according to 

 the Neumann method, W. Heubner (Biochem. Ztschr., 64 (1914), No. 4-6, pp. 

 S93-400). — Neumann states that 1 cc. of serai-normal sodium hydroxid is 

 equivalent to 1.268 mg. of phosphorus. This factor (0.553) was found too low, 

 0.57 giving figures more nearly correct. The specifications set down by Neu- 

 mann and Gregersen must be observed. 



On the factor to be used for the calculation of the phosphoric acid in 

 Neumann's method, S. L. Jodidi (Jour. Amer. Cheni. Soc, 37 (1915), No. 7, 

 pp. 1708-1710). — In connection with an investigation on the chestnut bark 

 disease, a careful redetermination of the factor employed in the Neumann 



