93] Atmung 349 



respired varies directly with the number of days the wheat remained in storage. 

 The temperature at which the grain is stored affeets the rate of diastatic action, 

 thus increasing the quantity of Substrate available to the respiratory enzyms. 

 This is indicated by the greater rate of respiration of wheat stored at room 

 temperature than that stored at the outdoor temperature during the winter 

 months. 6. Unsoundness of wheat caused by the freezing of the unripe plant 

 results in higher respiratory activity in the threshed grain. This was shown 

 by eomparing moderately and badly frosted wheats with sound wheat. The 

 frosted wheat respired more vigorously than the sound wheat. This was attri- 

 buted to the arresting of the synthetic processes on freezing, and subsequent 

 activities of the hydrolytic enzyms on thawing of the frozen wheat. The accu- 

 mulation of glucose as the result of starcli hydrolysis furnishes larger 

 quantities of Substrate to the respiratory enzyms. 7. Increasing temperatures 

 accelerate the late of respiration until 55° C is reached. As the temperature rises 

 the diastatic action upon starch increases. A point is reached, however, at 

 which the enzym activity diminishes. 8. Accumulation of carbon dioxid in the 

 respiration Chamber decreases the rate of respiration. The mean rate by four- 

 day intervals is highest for the first four days and diminishes materially in 

 successive periods. 9. Respiration is reduced in an oxygen-free atmosphere, the 

 ratio to that occuring in a normal atmosphere being about 1 to 2,5." 



594. Bezagu, Maurice. Variations de 1 a respiration des 

 e e 1 1 u 1 e s de 1 a f e u i 1 1 e a v e c 1 ' ä g e. (Compt. Rend. Acad. Sei. Paris 

 CLXIX, 1919, p. 701— 70-2.) 



595. Brooks, Matilda Moldenhauer. Comparative s t u d i e s o n 



respiration. VIII. The respiration o f Bacillus subtilis 

 in relation t o antagonism. ( Journ. of Gen. Physiol. 11, 1919, Nr. 1, 

 p. 5 — 55.) — Summary: „1. In relatively low concentrations of NaCl, KCl, and 

 CaClo the rate of respiration of Bacillus subtilis remains fairly constant for a 

 period of several hours, while in the higher concentrations, there is a gradual 

 decrease in the rate. 2. NaCl and KCl increase the rate of respiration of 

 Bacillus subtilis somewhat at concentration of 0,15 M and 0,2 M respectively; 

 in sufficiently high concentration they decrease the rate. CaCl2 increases the 

 rate of respiration of Bacillus subtilis at a concentration of 0,05 M and decreases 

 the rate at some-what higher concentrations. 3. The effects of salts upon 

 respiration show a well marked antagonism between NaCl and CaCU, and 

 between KCl and CaCh. The antagonism between NaCl and KCl is slight and 

 the antagonism curve shows two maxima. 



596. Haas, A. R. C. Effect of anesthetics upon re- 

 spiration. (Bot. Gaz. 67, 1919, p. 377—404, mit 7 Fig.) — Summary: 

 „When Laminaria is exposed to anesthetics (in sufficiently high concentration 

 to produce any result) the initial effect is an increase of respiration. This 

 may be followed by a decrease if the anaesthetic is sufficiently toxic. No de- 

 crease of respiration is observed when the concentration is too low to be 

 toxic. These results directly contradict the idea advocated by Verworn and 

 bis pupils that anesthetics act by decreasing respiration.'' — Siehe auch Ref. 

 in Bot. Ctrbl. 141, 1919, p. 265. 



597. Haas, A. R. C. Respiration afterdeath. (Bot. Gaz. 67, 

 1919, p. 347 — 365, mit 3 Fig.) — Summary: „The respiration of Laminaria 

 alter death may be considerably greater than in its normal condition. This- 



