Band 141. Nr. 16. XL. Jahrgang. IL Bd. Nr. 16. 



Botanisches Centralblatt 



Referierendes Organ 



der 



Association Internationale des Botanistes 

 für das Gesamtgebiet der Botanik. 



Herausgegeben unter der Leitung 

 des Präsidenten: des Vice -Präsidenten: des Secretärs: 



Dr. D. H. Scott. Prof. Dr. Wm. Trelease. Dr. J. P. Lotsy. 



und der Redactions-Commissions- Mitglieder: 



Prof. Dr. Wm. Trelease, Dr. G. Bonaventura, A. D. Cotton, 



Prof. Dr. C. Wehmer und Mag. C. Christelisen. 



roa zahlreichen Specialredacteuren in den verschiedenen Ländern. 



Dr. J. P. Lotsy, Chefredacteur. 



No. 41. 



Abonnement für das halbe Jahr 25 Mark 

 durch alle Buchhandlungen und Postanstalten. 



1919. 



Alle für die Redaction bestimmten Sendungen sind zu richten an: 

 Redaction des Botaniseben Centralblattes, Haarlem (Holland), Spaarnei7. 



Bailey, I. W. and W. W. Tupper. Size Variation in tra- 

 cheary cells: I. A comparison between the secondary 

 xylems of Vascular Cryptogams, Gymnosperms and 

 Angiosperms. (Proc. Amer. Acad. Arts & Sc. LIV. p. 149—204. 

 f. 1—6. Sept. 1918.) 



No absolute correlation between body size and cell size is 

 ound. In the main, the tracheary elements of secondary wood are 

 found to be largest in vascular cryptogams, shortest in typical 

 dicotyledons, and intermediate in gymnosperms — of which the 

 aberrant Gnetales simulate angiosperms in their vessels. An exten- 

 sive tabulation of data is given. Trelease. 



Brown, M. M„ The development of the embryo-sac and 

 ofthe embryo in Phaseolus vulgaris. (Bull. Torrey Botan. Club. 

 XLIV. p. 535—544. PI. 25, 26. 1917.) 



The author studied in several varieties of Phaseolus the deve- 

 lopment of the macrospores, the embryosac, the embryo and the 

 endosperm. No difference between the different varieties was found. 

 As the only description of the embryo-sac or embryo of Phaseolus, 

 known to the author, is that by Guignard in the year 1881, the 

 results of the researches are dealt with in this review as the author 

 summarizes them at the end of her paper. 



A large hypodermal cell is early differentiated in the ovule; 

 this either functions as the macrospore mother cell or possibly 

 divides once, one of its daughter cells being the macrospore 

 mother cell. 



Botan, Centralblatt. Band 141. 1919. 16 



