St os Be oa Teo ee 
. ne 
1910] ’ CURRENT LITERATURE 317 
-Gauitzky and WassILjEFF’ have studied the effect of boiled extract of 
wheat and bean seeds upon the respiration of living and killed (by treatment 
with acetone) wheat seedlings. In agreement with various other workers, 
they find that the extracts greatly increase the CO, output in both living and 
killed seedlings: 60 per cent in normally acid cultures, 117 per cent in neutral 
cultures, and 86 per cent in slightly alkaline cultures. The authors raise the 
question, “Is the stimulative action due to food materials supplied by the 
extract, or to bodies of the nature of co-enzymes?” L.and N. IwanorF have 
assumed that the stimulation is due to the action of organic or inorganic 
phosphates on anaerobic respiration, analogous to the action of these bodies 
as co-enzymes for zymase. The authors find that peptone, glycerin, mannit, 
sodium lactate, quinic acid, sodium chlorid, and ferric chlorid have very little 
or no effect upon the respiration of the seedlings. Dextrose, saccharose, 
maltose, and sodium carbonate give a slightly increased CO, output, about 20 
per cent. Arabinose and ferrous sulfate give a somewhat greater stimula- 
tion of the extracts. The authors consider it especially interesting that prob- 
able intermediate products of alcoholic fermentation, lactic acid and sodium 
lactate, have no stimulative effect. This is quite in contrast with conceptions 
of Kostyrscuew. The authors are to extend the tests to various other sub- 
stances, especially to phosphates, to see whether they will give the amount 
of stimulation shown by the extracts. One naturally wonders to what extent 
bacterial action may increase the CO, output. So far as methods are described, 
one certainly cannot be assured that such has not happened.—WILLIAM 
CROCKER 
Heliotropism and geotropism.—GUTTENBERG* has already shown, contrary 
to the earlier conception of most writers, that the effect of the geotropic stimulus 
of a candle power. RICHTER? called the results of GUTTENBERG into question, . 
7 Gauitzky, KATHERINE, und Bigatti. Vera, Zur Atmung der Weizenkeime. 
Ber. Deutsch. Bot. Gesell. 28: 182-187. 
* GurrenBeRG, H. R. v. Ueber das ee mmenwirken von Heliotropismus und 
Geto i in Sula Pflanzenteilen. Jahrb. Wiss. Bot. 45:193-231- 
Igo’ 
9 Ricurer, O., Ueber das Zusammenwirken von Heliotropismus und Geotropis- 
mus. Jahrb. Wiss. Bot. 46 2481-502. 1909. 
