ALIKICULTURAL CHEMISTRY. 705 



^(•ihmmI i)roporti()u of (ho several ainiiio-iicids, but also to the total (Hiautity 

 obtained from each of these albumius. . . . 



"It is iii)t iuiprobahle that lefiuineliii is a constituent of the i)h.vsioloj.'icall.v 

 active tissues of the seed, rather than a reserve food substance for the (h'velopinj; 

 seedling. 



•"I'his supposition In regard to leucosin is supported by the fact that this 

 all)nniin is located almost entirely in the embryo of the seed and that it resem- 

 bles more closely, both in properties and composition, the proteins of physiolog- 

 icjilly active tissues of animals, than those which unquestionably form the 

 reserve food protein of the endosperm of other seeds. 



"As the lejinminous seeds do not contain a sharjjly differentiated embryo and 

 endosi)erm, but are composed of tissues which combine the functions of both, 

 it is not possible to locate any one of their proteins in any particular part of 

 these seeds. The just-mentioned similarity, however, of legumelin to leucosin 

 is sujifrest i ve of similarity also in their physiological functions." 



On the influence of temperature upon the solubility of casein in alkaline 

 solutions, T. P.. lioinarrsox (Jour. Biol. Clicni., .7 ( I'JOS), \o. ^-.i, pp. I'll- hi.',). — 

 The author has continued his researches ou the chemical properties of caseir 

 (E. S. R.. IS, p. 87.3). 



" The solubility of the casein in alkaline solutions is considei-ably augmented 

 by carrying out the jirocess of solution at temperatures above 40° ('. 



" It is pointed out that this fact is not in harmony with the view that a rise 

 in temperature increases the degree of hydrolytic dissociation of solutions of 

 the caseinates. 



" In explanation of this fact and of the increase in alkalinity and electrical 

 conductivity of caseiuate solutions upon heating, which were observed by 

 Osborne, it is suggested that the inMuence of heat upon proteins consists, among 

 other effects, in shifting equilibria of the type : IIXOH+IIXOII^HXXOII+H,0 

 in the direction of higher com])lexes, and that heat coagulation is a result of 

 reiK'ated condensations of this type. 



"The solubility of casein in solutions of various concentrations of jtotassiuni 

 hydroxid. lithium hydroxid, and calcium hydroxid at. various temperatures has 

 been determined." 



The establishment of the equivalent weight of casein and a new method 

 for its estimation, (i. T. ^Iatthaiopoulos (Ztschr. Ainth/t. Cliciii., .',7 (IDOS), 

 .Vo. 8, pp. .','.i.i-oOI ; ahs. in Annli/st, 33 (1908), No. 390. pp. 365. 36"6').— The 

 author's niethcjd is based on the fact that casein behaves like an acid toward 

 l»henolphthalein. Dilute sulphuric acid is added to milk until the casein is 

 coagidated. The filtrate is titrated with sodium hydroxid and its amount 

 conipare<l with the amount recpiired when the casein is not removed. Using 

 this iiii'tlioil the author has determined the equivalent weight of casein to be 

 i.i:;i..-,. 



Medico-legal studies of starch by means of polarized light, M. IIkrman 

 (//(//. Sor. Chim. lidff., 22 (1908), .Yo. 8-9. pp. 3.',0-3-'i2).— The author discusses 

 the im|K)rtance of this method of analysis. 



The determination of pepsin with the report of a new method, K. Fui.n and 

 I.. A. I.KvisoN (.\ni<r. Mai., ii. .ttr.. .! (I'.IOS). \o. 2. p. ')7-(!.i). — The titration 

 method for estimating |>ep^i". which tli«' authors proj»ose, involves the use of 

 a 1 per <'ent solution of e<lestin in dilute hydrochloric acid. The ajiplicat i(»n of 

 tile method to problems of theoretical and practical interest is discussed and 

 from the data |)re.seuttil the authors conclude that the method gives more 

 satisfactory results than the older methods and is to be recommended for exact 

 work. 



