No. 3, July, 1921] PHYSIOLOGY 323 



seem to have little influence on the formation of glycogen. The optimum for the formation 

 of glycogen in brewer's yeast is around 30°C. Cells kept at high temperatures for some time 

 and then forced to adapt themselves to low temperatures showed a very low rate of propaga- 

 tion (20-30 cells in 3 days) while yeasts of the same species grown at high temperatures for 

 some time produced 300,000-350,000 cells in the same period. The formation of esters is slower 

 at lower temperatures (10°C.) than at higher temperatures (30°C.). The shape of the cells 

 is influenced by variations in temperature; the former shapes being assumed, however, when 

 subsequently grown at optimum temperatures. In pigment producers the production of 

 coloring matter is most pronounced at low temperatures. Giant colonies show only gradual 

 changes with variations in temperature, but are raised above the substratum much more when 

 grown at low temperatures. Softening and liquefaction of yeasts takes place more rapidly 

 as the temperature increases. In determinations of the thermal death point Willa saturnus, 

 Schizosaccharomyces Pomhe, Saccharomyces Logos, and Saccharomyces thermantitonum were 

 found more resistant. — Anthony Berg. 



RADIANT ENERGY RELATIONS 



2195. Russ, Sidney. Growth and division of cells as affected by radiation. Sci. Prog. 

 [London] 13: 605-613. 1919. — This is a discussion of the eff'ect of x-rays on the growth of tu- 

 mors, with special reference to the susceptibility of the cells in different stages of growth to 

 radiation. — /. L. Weimer. 



TOXIC AGENTS 



2196. Harden, Arthur, and Francis Robert Henly. The effect of pyruvates, alde- 

 hydes, and methylene blue on the fermentation of glucose by yeast juice and zymin in presence of 

 phosphate. Biochem. Jour. 14: G42-653. Fig. 1-2. 1920. — The investigators take as a thesis 

 the fact noted by various workers that a-ketoacids and aldehydes have an activating effect 

 upon yeast fermentation, particularly at the commencement of the reaction, and that this 

 effect has been noted especially in experiments made with maceration extract containing a large 

 amount of mineral phosphate. The question arose as to whether this was a general stimula- 

 tion effect or a more specialized acceleration of the reaction in the presence of free mineral 

 phosphate. In general, the results show no marked activation following the addition of 

 aldehydes to fermenting mixtures of yeast juice or zymin with glucose. If a suitable amount 

 of phosphate be added, the effect of the aldehyde is to greatly diminish the time required for 

 the maximum gas production, and likewise a higher maximum is attained. On completion 

 of the esterification of the phosphate, the rate again diminishes both in the presence and ab- 

 sence of aldehyde and the total evolution is not greatly different in the 2 cases. Similar 

 effects were obtained with pyruvates. The effect varies with the concentration of the alde- 

 hyde and is common to, but not equal in, the 4 aldehydes tested, formic, acetic, propionic, 

 and butyric. The results suggested an effect due to a lack of an acceptor for hydrogen. 

 Methylene blue, readily reducible by hydrogen, produced the same effects as the aldehydes. 

 In the light of these results, the final stage of alcoholic fermentation of sugar is held to be 

 the reduction of the acetaldehyde produced by the decomposition of pyruvic acid, the pro- 

 duction of this latter from sugar being only possible when some acceptor for hydrogen is avail- 

 able. This acceptor is normally supplied by acetaldehyde produced at a later stage of 

 the reaction. — A. R. Davis, 



2197. Willaman, J. J. Toxicity of alpha-crotonic acid. [Rev. of: Skinner, J. J., and 

 F. R. Reed. The influence of phosphates on the action of alpha-crotonic acid on plants. Amer. 

 Jour. Bot. 6: 167-180. 1919 (see Bot. Absts. 3, Entry 437).] Bot. Gaz. 69: 96. 1920. 



MISCELLANEOUS 



2198. Carles, Pierre. Sur la casse bleue des vins. [The "blue cassia" of wine.] 

 Compt. Rend. Acad. Sci. Paris 169: 1422-1423. 1919.— The treatment of this so-called "dis- 

 ease" of wine by the addition of an organic acid, either tartaric or citric, is recommended. — 

 R. W. Webb. 



