AGRICULTUEAL CHEMISTRY AGEOTECHNY. 503 



merely heat-denatured protein obtained in a loose state of aggregation by the 

 method employed." 



The lecithin of egg yolk, J. D. Riedel (Abs. in Chem. ZentU., 1912, I, No. 

 23, p. 1794; Jour. Chem. 8oc. [London], 102 {1912), No. 600, I, p. 74//).— A 

 preparation was obtained from egg yolk, free from cholesterol and foreign 

 proteins, by extraction with methyl alcohol. " The formula : 0R-CH2-CR'(0H). 

 CH2P03(OH)-C2H4-NMerOH, is proposed for lecithin, R and R' being alipathic 

 acyl groups, of which palmitic, stearic, oleic, and linoleic acids have been 

 recognized." 



Forms of sugar found in common fruits, F. Thompson and A. C. Whit- 

 TiEE (Proc. 8oc. Hort. ScL, 9 {1912), pp. 16-22). — It is pointed out that it is as 

 important to know how much levulose and dextrose is contained in a fruit as 

 the quantity of sucrose present, and the reducing and nonreducing sugars in 

 different varieties of apples, peaches, tomatoes, pears, strawberries, sweet 

 potatoes, bananas, plums, quinces, watermelons, persimmons, and grapes were 

 studied. In some cases the green and ripe fruits were examined. The dominant 

 type of sugars varies with different fruits, and the common practice of express- 

 ing the reducing sugars as invert sugar falls far short of the truth in many 

 instances. Invert sugar is a mixture of equal amounts of levulose and dextrose 

 and occurs as such only in the case of the peaches, one of the grapes, bananas, 

 strawberries, and Stone tomatoes and persimmons. 



" Levulose is the dominant sugar in apples, pears, quinces, Yellow Pear 

 tomatoes, watermelon, and three of the grapes, and far exceeds the dextrose 

 in the apples, pears, and quinces. With the sweet potato, plum, and one 

 variety of the grape, the dextrose exceeds the levulose, but only in the case of 

 the plum does it far exceed it, and in this case it is lower than the sucrose. 

 One analysis of immature persimmons showed an excess of dextrose over 

 levulose, so it can scarcely be said that dextrose is the principal sugar present 

 in any case. Sucrose is the principal sugar in peaches, plum, and sweet 

 potato." 



In 4 out of 5 grapes, 0.5 per cent of sucrose was present in the juices. From 

 the figures, with one exception of the peach, it would seem that the dominant 

 sugar is the first one to appear in the green fruit, and remains in excess until 

 maturity. In the ripe peach, however, the sucrose finally exceeds the per- 

 centage of invert sugar. A sample of persimmons ripening in the laboratory 

 showed a complete inversion of the sucrose. " One sample of green grape juice 

 showed no sugar of any kind when analyzed by the optical method, but gave 

 0.76 per cent of invert sugar by the copper reduction method. Twenty days 

 later the juice of grapes from the same vine gave 0.64 per cent by the optical 

 method and 1.2 per cent by the reduction method. It is evident from these 

 results that grape juice contains reducing substances other than levulose or 

 dextrose which are not removed by the ordinary process of clarification and 

 [this] emphasizes the need of other methods for the determination of these 

 sugars." 



The plant alkaloids, T. A. Henry {Philadelphia, 1913, pp. F//-f.'/66). — This 

 is a description of plant alkaloids, not only as to the properties and chemistry 

 of these products but also as to their occurrence, methods of estimation, and 

 physiological action. The various alkaloids are considered by groups, and an 

 appendix presents recent work on alkaloids. 



The amount of nicotin in the tobacco plant, E. Chuard and R. Mellet 

 {Schioeis. Wchnschr. Chem. u. Pharm., .50 {1912), No. 31, pp. //7M7// ) .—After 

 pointing out the increasing importance of the tobacco plant as a source of 

 nicotin for insecticidal purposes, the results of an investigation in regard to the 

 amount of nicotin present during the various stages of growth are given. 



