132 EXPERIMENT STATION RECORD. [Vol.43 



account of both tlie physical and clieniical aspects of energy supply for cell 

 growth. 



. Tlie structure of protoplasm, R. A. Hakper (Amcr. Jour. Dot., 6 (IHI'J), 

 No. 7, pp. 21S-300). — This review concludes by expressing the opinion of tlie 

 author that the older attempts to solve the problem of protoplasmic behavior by 

 the assumption that protoplasm is composed of physiological units, biophores, 

 determiners, plasomes, pangens, etc., and the newer conception that its essential 

 elements are unit factors are being merged in tlie conception that the structure 

 of protoplasm is the structure of the cell as an organized system and itself the 

 unit in all the complex interactions by which the egg develops into the 

 specialized differentiated many-celled organism. 



The origin and nature of the mucilage in the cacti and in certain other, 

 plants, F. E, Lloyd {Amer. Jour. Bot. 6 (1919), No. 4, pp. 156-1G6) .—The 

 autlu)r finds that mucilage in the cacti, mallows, and tragacanth arises within 

 specialized parenchyma cells by hydrolysis of the cellulose wall, which is not 

 secondarily thickened. The mucilage, which shows lamination determined by 

 water content, is not laid down as a secondary layer. It is not secreted within 

 the protoplast, nor is it yet a secretion thrown out as mucilage from the outer 

 surface of the protoplasm. The lamination may be predetermined by the 

 apposed layers of cellulose in the original cell wall. The mucilage adsorbs 

 certain dyes with great vigor, others with lesser and different degress of 

 vigor, and still others not at all. The vi.scosity of the mucilage is lowered by 

 tho.se dyes which are adsorbed, at a rate and to an extent in direct relation to 

 the degree of adsorption. 5 



Authocyanin of Beta vulgaris, F. M. Andrews (Proc. Ind. Acad. Sci., 1917, ^ 

 p. 161). — The anthocyanin of B. vulgaris affords one of the examples where the % 

 pigment forms in the subterranean parts. A strong solution of such antho- f. 

 cyanin will preserve its normal color in a test tube placed in darkness for ■^• 

 more than a week. In direct sunlight it will retain its normal bright color for 

 a week or more, until disoi-ganized by bacterial action, which change finally 

 occurs in the anthocyanin solution in the dark. 



Chlorophylless wheat plants, B. Kalt {Zt.-;chr. PflanzenzucM., Jf {1916), No. 

 2, pp. 1^/3-150). — Morphological and physiological .studies on barley and rye 

 are reported, which are said to agree as to general results with those reported 

 by Nilsson-Ehle (E S. R., 31, p. 329). 



The temperatuiocoeflicient of photosynthesis: A reply to criticism, A. M. 

 Smith {Ann. Bot. [London], 3S {1919), No. 133, pp. 517-536, figs. 2).— This is 

 a discussion of recent contributions on the relations between photo.syiithesiSj 

 and temperature, in particular those by Brown and Heise (E. S. R., 39, p. 225),; 

 and by Brown alone (E. S. R., 41, p. 429). 



Theory regarding jihototropism, C. E. B. Bremekamp {Rcc. Trav. Bot. 

 N^erland., 15 {1918), No. 2, pp. 123-184, figs. 14).— Two factors are supposed t 

 operate in connection with the phenomenon of phototropism, namely, the differ 

 ence between the antagonistic portions as regards number of light-sensitivej 

 areas and the time within which this difference is maintained. A growth- 

 promoting influence may be exerted by those portions within which a growth 

 inhibiting substance may be produced under illumination. 



The transmission ot phototropic stimulation, A. Paal {Jahrl). Wiss. Bo 

 [Pringsheini'], 58 {1918), No. 3, pp. 406-458, pi. 1, figs. 9). — A detailed accoun 

 is given of the author's experiments on the transmission of stimulation pasi 

 interruptions (with simple sectioning or with colloid layer interposed). Thj 

 course ot the stimulus was studied, as wei-e also wound curvature and gi'owtl 

 regulation in this connection. 



