326 W. Wendler: Chemische Physiologie 1917— 1919 [7(1 



463. Jorgensen, Ingvar and »Stiler. Walter. C a r b o n assimilatio n. 

 A Review o f recenl work o n tlie pigments o f t h e g r e e n 

 1 e a f and the processes connected \v i t li t h e in. (New Phyto- 

 logist 16, 1917, p. 24—45, p. 77—104.) — Abschnitt VI b e li a n d e 1 1 

 Energy relations in carbon assimilation: .4. General remarks. 



B. Quantitative estimation of carbon assimilation by means of the products. 

 ('. Quantitative determination of the heat of combustion of the products of 

 assimilation. D. Quantitative measurement of the radiant energy incident on 

 the leaf and the utilisation of this energy. E. Assimilation in relation to radiant 

 energy of different wave lengths. Abschnitt VII: Theories o f car- 

 bon assimilation. A. General remarks. B. Hypothesis of Bayer. 



C. Suggestion of Van't Hoff. D. Suggestion of Siegfried. E. Theories of Will- 

 stätter. Abschnitt VIII. C o n c 1 u ding r e m a r k s. Literature cited. 



164. Mason, T. C. n s o m e f a c t o r s affecting the c o n c e n - 

 tration of electrolytes in the leaf-sap of Syringa vulgaris. 

 (Sei. Proc. Roy. Dublin Soc, N. S., 15, 1919, p. 651—666.) - - Summary: 1. The 

 determination of the concentration of the electrolytes of the cell by means of 

 conduetivity observations has been found unsatisfactory, unless allowanee is 

 made for the viscosity of the sap. Methods of making a correction for the 

 viscosity liave been described. 2. The osmotic pressure of the cell is frequently 

 mainly due to electrolytes; but the presence of solutes which are neither 

 electrolytes nor sugars is not exeluded. 3. Considerable fluetuations in the 

 concentrations of electrolytes in the leaf-sap of Syringa vulgaris trees growing 

 in different localities have been indicated. 4. A tendency for the concentration 

 of electrolytes to vary inversely with that of the non-electrolytes has been 

 found. 5. It is suggested that these fluetuations are associated with the rate 

 of carbon assimilation, which determines the rate at which electrolytes are 

 removed from Solution in metabolism. 



465. 31aze, P. et Ruot, M. Recher ch es s u r l'assimilati o n d e 

 1 ' a c i d e lactique par 1 e s levures et sur 1 a produetion 

 d " a c i d e p y r u v i q u e par 1 e s levures et 1 e s o i d i u m s. (Compt. 

 Rend. Soc. Biol. Paris LXXX, 1917, p. 336—339.) — Nicht nur Schimmelpilze, 

 sondern auch Hefen und Oidien vermögen Milchsäure zu assimilieren und 

 Brenztraubensäure zu bilden. („Pilze 1917" Nr. 444.) 



466. Meyer, Arthur. Das w ä h r e n d des Assimilati o n s p r o - 

 z e s s e s in den C h 1 o r o p a s t e n entstehende Sekret. (Ber. D. 

 Bot. Ges. 35, 1917, p. 586—591.) — Ref. in Bot. Ctrbl. 141, 1919, p. 164—165. 



467. Meyer, Arthur. Die chemische Zusammensetzung des 

 Assimilationssekretes. (Ber. D. Bot. Ges. 35, 1917, p. 674—680.) - 

 Verf. versucht zu zeigen, daß der a, /J-Hexylenaldehyd und seine Verwandten 

 ans dem Assimilationssekret stammen. Ob noch andere Körper an der Zu- 

 sammensetzung des Sekretes beteiligt sind und bejahendenfalls welche, müßten 

 erste weitere Untersuchungen lehren. Vgl. die Besprechung von Czapek in 

 Ztschr. f. Bot. 11, 1919, p. 69—72 



468. Robbins, William J. D i r e c t assimilation o f organic 

 c a r b o n b y Ceratodon purpureus. (Bot. Gaz. 65, 1918, p. 543 — 551, mit 5 Fig. ) 

 — Summary: „1. Under the conditions of the experiments reported organic 

 carbon in the form of levulose, glucose, galactose, lactose, cane, sugar, and maitose 

 is absorbed and utilized by Ceratodon purpureus. 2. Starch is formed in the dark 

 from levulose, glncose, galactose, lactose, cane sugar, and maitose. 3. Mannite, 



