883 



by the action of the current, which could be observed in all plants, did not 

 always remain the same. At times if was toward the negative pole ; in 

 other cases, toward the positive pole. 



In opposition to the cultural experiments with barley, published earlier 

 by Lowenherz and confirmed later by Gassner, which prove an injurious 

 effect of the electric current, the first named author now reports favorable 

 results (Z. f. Pflanzenkrankh. 1908, Part i). With a weaker current he 

 found a hastening of the growth of a seedling; the injurious action began 

 only with an increase of the current. 



Page 524. In the reports of the Hatch Experiment Station of the 

 Massachusetts Agricultural College (cit. Z. f. Pflanzenkrankh. 1908) may 

 be found observations on the leaf blight of conifers and other evergreen 

 trees as the result of winter and spring frosts. The trees show the blight 

 usually only On one side, which corresponds to the prevailing direction of 

 the wind. If dry winds blow with a high temperature at a time when the 

 soil is still frozen, the plants cannot find sufficient compensation in the 

 frozen soil for the increased transpiration and the leaves dry up. This is 

 the same theory which found expression earlier as explanation for the drop- 

 ping of pine needles. The native conifers suffered less, in case they did not 

 stand on unfavorable soil, when compared with the imported varieties of 

 Picea, Abies, Juniperus, Taxus, Buxus, etc. 



Page 675. According to Stocklasa's investigations, Ueber die glykoly- 

 tischen Enzyme in Pflanzenorganismus, Z. f. physiol. Chemie, Vols. 50 and 

 51, 1907, the anaerobic respiration is an alcoholic fermentation in which a 

 certain amount of lactic acid has formed together with alcohol and carbon 

 dioxid. This holds good also for frozen organs (beets, potatoes, etc.). 

 Zymases and lactacidases are, therefore, not destroyed by the freezing. 

 Lactic acid, alcohol, carbon dioxid, acetic and formic acid are also formed 

 by enzymes in living plant and animal cells. The decomposition of the 

 hexoses by glycolytic enzymes is normally completed without the cooper- 

 ation of bacteria. In the precipitates procured from pure plant juices by 

 absolute alcohol and ether, the author found fermentation enzymes which 

 produced a lactic acid and alcohol fermentation in the glycose solution ; in 

 this process with easy access of oxygen definite amounts of acetic and 

 formic acid are always formed. 



Page 677. Fallada's investigations (Oesterr. Ungar. Zeitschr. f. 

 Zucherindustrie u. Landw. Part V, 1907) on the white leaf conditions of 

 beets favor the theory that the white parts of the leaf remain in a younger 

 developmental stage and with a scantier cell content and are more suscep- 

 tible to the influence of light and heat than are the green organs. The 

 etiolated leaves had a greater water content ; the smaller amount of organic 

 substances gave a relative increase of protein especially of the non-albu- 

 minous nitrogen compounds. The potassium and phosphoric content was 

 greater; the calcium and silicic acid content was smaller. 



