272 Physiologie. 



Darbishire, 0. V., An Apparatus for Observing the 

 Transpiration Stream. (Bot. Gaz. Vol. XXXIX. May 

 1905. p. 356—364. 2 iig. in text.) 



A description of an arrangement vvhereby in observing 

 the relation between shoot suction and root pressure, the two 

 portions of the plant are not wholly separated, but are con- 

 nected by a continuous piece of apparatus, interpolated be- 

 tween the root and shoot end. This the author calls a pino- 

 meter. The apparatus is a simple one, but can be best 

 understood by reference to the figures. 



H. M. Richards (New York). 



Dean, A. L., On Proteolytic Enzymes. I. (Bot. Gaz. Vol. 

 XXXIX. May 1905. p. 321—339.) 



Finds the presence of a protease in the leaves of Spinacia 

 oleracea and Brassica oleracea ; in the blossoming heads of 

 Daaciis carota ; in the leaves and unripe seeds of Castanea 

 sativa americana ; in the etiolated seedlings of Phaseolus Miingo\ 

 in the seeds and seedlings of Cucurbita maxima ; and in the 

 seeds of Cucurbita Pepo. The paper is chiefly concerned, 

 however, with the study of the proteases in Phaseolus vulgaris. 

 Found in all stages of germination of the seed that the cotyle- 

 dons contain an ereptic enzyme, but that at no time was an 

 enzyme capable of attacking the stored proteids obtained. The 

 ereptase, however, was isolated and was found to act on the 

 proto-proteose, the hetero-proteose, and the deutero-proteose, 

 separated from Witte peptone, but was wholly inactive on 

 phaseolin of the bean, excelsin of the Brazil nut, edestin of 

 hemp seed, and boiled fibrin. 



Concluded that the stored proteid in the bean must undergo 

 cleavage into simpler substances before its utilization, but what 

 effects the cleavage or what part the ereptase plays is unsolved. 



H. M. Richards (New York). 



Leclerc du Sablon, Sur les effets de la decortication 

 annulaire. (C;. R. Acad. Sc. Paris. 5 juin 1905.) 



Les experiences ont porte sur des Poiriers, des Coig- 

 n assiers et des Fusains du Japon äges de 3 ä 4 ans. 

 Un premier lot d'arbres a ete decortique le 9 f^vrier avant le 

 depart de la Vegetation; un second lot le 8 mai lorsque les 

 premieres pousses etaient formees. Un troisieme lot servait de 

 temoin. A des intervalles de deux mois environ, des arbres 

 appartenant ä chacun des trois lots etaient recoltes et analyses 

 comparativement. Les racines des arbres döcortiques en fevrier 

 ont d'abord plus de rdserves que Celles des arbres temoins, et 

 leurs tiges moins de reserves que les tiges des temoins. Aprfes 

 le mois d'avril ä la suite de l'assimilation par les feuilles, c'est 

 l'inverse qui a lieu. 



Dans les arbres decortiques en mai la racine est des le 

 commencement plus pauvre que dans les temoins. Plus tard 



