Physiologie der Zellen, Gewebe und Organe. 13 



Der Vortrag gibt einen vortrefflichen knappen Abriß aus dem Gebiete des inter- 

 mediären Stoffwechsels. Seine Lektüre kann dringend empfohlen werden. Dohrn. 



24) Blackmai!, V. H., and Paine, S. F., A recording transpirometer. 

 In: Annais of Botany, Bd. 28, Heft 1, S. 109 — 113. 1914. 



This Instrument will record autoinatically the amount of water lost by 

 the plant. In previous instruments for this purpose, such as that of Ganong, 

 metal balls were released at intervals when a given amount of water had evapo- 

 rated. In the apparatus here described. water drops are used instead of metal 

 balls, and the water is added directly to the soil. In this way the combined 

 weight of pot and plant, as well as the ainount of water in the soil, are kept 

 constant. The apparatus consists of (l j a water-reservoir with a tube supplying 

 drops of constant size. (2) an electric device to draw the tube back and forth, 

 (3) a balance bearing the plant, and (4) a revolving drum with electric recording 

 pen. In this way a record is made every time a drop passes through the tube. 

 and the varying distances between these marks show the frequency of tran- 

 spiration. Gates. 



25) Kuisrht, K. C. and Priestley. J. H.. The respiration of plants under 

 various electrical conditions. In: Annais of Botanv. Bd. 28, Heft 1, 

 S. 135 — 161, 1914. 



It has been known that an electrical discharge from an overhead System of 

 wires causes an acceleration in the growth of various crops, and an increase in 

 the yield in ruany cases. The attempt is made to analyze the effect of this dis- 

 charge on plants grown in the laboratory. and thus to determine the cause of 

 the acceleration. As an instance of such results. English wheat when electrified 

 gave an iucrease in yield of 29 ° . while Canadian wheat gave an increase of 

 39 ° in the open in 1906. Strawberries. tomatoes. cabbages etc.. are known to 

 show similar increase in yield. 



By experiment it was found that electrical discharge caused an increase in 

 CÜ 2 -production in the plant, but that this was accounted for by the incidental 

 rise in temperature. Direct currents of an intensity 10 -6 to 10 -4 amperes 

 have no effect on the respiration of peas except that due to rise of temperature. 

 The proportion of these currents traversing the peas was very small, because 

 most of it was taken by the water film on the seeds. Overhead discharge of a 

 current less than 3 X 1<»~ 6 amperes has no effect on respiration. Higher cur- 

 rents produced a deflnite increase in CO., production due to rise in temperature. 

 In the rield. the explanation of the acceleration effect must be based on other 

 processes in the plant. Gates. 



26) Javoilier, M. et Tcherniroutzky, )[""' H.. Influence coniparee du 

 zinc. du cadmium et du glucinium sur la croissance de quelques 

 Hvphomvcetes. In: C. R. Acad. Sc. Paris. Bd. 157. Heft 23. S. 1173-1176. 

 1913. 



Les auteurs rappellent que leurs recherches anterieurs leur ont permis de 

 conclure que le zinc. ä tres petites doses. favorise considerablement la croissance 

 du Sterigm \tocystis nigra. Aucun element ne peut le remplacer parfaitement. 

 aucun n'est vis-a-vis du Sterigmatocystis, un aussi puissant cataiysateur, le cad- 

 mium preseutant seul. avec le zinc, une certaiue analogie d'action. Les auteurs 

 ont examine egalement quelle est l'infiuenee du zinc sur divers autres hvphomv- 

 cetes tels que: Poeeilomyces carioti, Penicülium gtaucum, PmicxUium caseicohun, eu 

 operant en cultures pures, et en evitant avec soin Tintroduction involontaire de 



