710 EXPERIMENT STATION RECORD. 



which the author recommends for determuiing the lecithin content of medicinal 

 preparations. 



Chromophylls in the plant and animal world, M. S. TsvffiT {KhromoflUy 

 V rasiltcVnom i zhivotnom miirQ. Warsaw, 1910, pp. 379, pis. 5; rev. in Zhur. 

 Opytn. Agron. (Riiss. Jour. Expt. Landw.), 11 {1910), No. 5, pp. 766-768). — 

 Besides an exhauslive and critical survej' of the literature, this monograph 

 contains a new method for isolating chlorophyll in the original, unaltered form 

 by adsorption. 



Besearches in regard to the presence of rice or darnel in wheat flour, E. 

 Collin and Terrier (Ann. Falsif., 4 {1911), No. 36, i)p. J,93-o03, figs. 2).— A. dis- 

 cussion in regard to the presence of rice and darnel {LoHum tcmulcntiim) in 

 wheat flour, the characteristics of rice and darnel flour, and. the method by 

 which these foreign substances gain entrance into the wheat flour. A method 

 is proposed for detecting these adulterations and impurities. 



Besearches in the value of potato varieties, P. Berthault {Sci, Amer. Sup., 

 72 {1911), No. 1878, p. 423). — This article, which deals with the use of the micro- 

 scope in selecting stock for different purposes, is based on the assumption that 

 the cells which surround and hold the starch grains are an index as to the 

 quality of the tuber. The author has therefore devised, a method which he 

 calls the cellular-density method. 



The edible varieties show very small and numerous cells, while potatoes which 

 are to be used for starch making, etc., are larger and less compact. 



Invertase and diastase in honey, T. von Fellenberg {21itt. Lehensm. Untcr- 

 such. u. Hyg., Schweiz. Osndhtsamt., 2 {1911), No. 6, pp. 369-377). — Diastase 

 and invertase were found to be present in honey. This ix)int, however, has 

 already been noted by Langer, Auzinger, and Moreau (E. S. R., 22, p. 512; 23, 

 p. 307; 25, p. 412). Invertase was present in a greater quantity. 



The author finds that precipitating the enzyms from honey with alcohol does 

 not yield the total amount of enzym actually present. In order to obtain a 

 figure which is not infiuenced by this error, the author recommends examining 

 the enzyms in their natural substratum. The possibility of a hydrolysis of the 

 dextrin of honey, which is, according to Barschall, a hexatriose, that is, a group 

 of stereoisomers having trioses of varying rotations, must also be considered, as 

 dextrin is not hydrolyzed by honey invertase. Honey diastase was found to 

 exert its greatest activity upon potato starch, and. a somewhat less one upon 

 honey dextrin. The acids_ present in honey had very little influence uix»n the 

 inverting process. Honeys which stand for a time lose some of their inverting 

 capacity. 



A polariscopic method for the determination of malic acid and its ap- 

 plication in cane and maple products, P. A. Yoder {Jour. Indus, and Engin. 

 Chan., 3 {1911), No. 8, pp. 563-574, figs. 2).— A detailed description of a method 

 previously noted (E. S. R., 24, p. 612). 



Cocoa and chocolate: Their chemistry and manufacture, R. Whymper 

 {Philadelphia, 1912, pp. XI+327, pis. 13, figs. i9).— This treatise, according to 

 the preface, is designed to provide a standard work dealing with cacao from 

 its growth until it is manufactured into cocoa and chocolate. Part 1 deals with 

 the history, botany, and agriculture of cacao, part 2 with the manufacture of 

 chocolate and cocoa powders, and part 3 with the general and analytical chem- 

 istry and microscopy of cacao products. 



The arsenic content of shellac and the contamination of foods from this 

 source, B. H. Smith {U. 8. Dept. Agr., Bur. Chem. Giro. 91, pp. 4).— Among 

 other substances orpiment is generally added to shellac in India for giving the 

 straw-yellow color characteristic of the higher grade of goods and at the same 

 time to make the shellac opaque. As shellac is often used for coating the 



