Band 141. Nr. 18. XL. Jahrgang. IL Bd. Nr. 18. 



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. C. Bonaventura, A. D. Cotton, 



Prof. Dr. C. Wehmer und Mag. C. Christensen. 



von zahlreichen Specialredacteuren in den verschiedenen Ländern. 



Dr. J. P. Lotsy, Chefredacteur. 



No. 43. 



Abonnement für das halbe Jahr 25 Mark 

 durch alle Buchhandlungen und Postanstalten. 



1919. 



Alle für die Redaktion bestimmten Sendungen sind zu richten an: 

 Redaction des Botanischen Centralblattes, Kaarlem (Holland), Spaarnei7. 



Whepry, E. T., The reactions of the soils supporting the 

 o-rowth of certain native Orchids. (Journ. Wash. Acad. 

 Sei. VIII. 8. p. 589—598. Nov. 4, 1918.) 



Except for species of Cypripedium and Orchis, all of the Orchids 



investigated affeet an aeid soil. Trelease. 



Palm, B. and A. A. L. Rutgers. The embryology of Aucuba 

 japonica. (Rec. Trav. bot. neerl. XIV. p. 119-126. 1917.) 



Though it was known, that the female Japanese Aucuba, intro- 

 duced into Europe for its decorate leaves (1783), only then began 

 to produce the beautiful red berries, when male individuals were 

 brought over from Japan (1860), ^some authors have supposed the 

 possibility that its fruits would develop apogamously, a female 

 plant having given berries though male plants were entirely absent. 

 The authors have made a many isolation-experiments and artificial 

 pollinations. that indicate without doubt the impossibility of apoga- 

 mous development of the fruit and the necessity of pollination. 



Also have they confirmed these experiments microscopically, 

 by fixing and cutting pollen and embryosacs of Aucuba japonica. 

 The chromosome number in the second devision of the embryosac 

 mother cell and in pollentetrads was found as to be 18; the nucle'i 

 of root-tips gave the 2x number of chromosomes repeatedly as 36. 

 In the endosperm the exaet number was not made out with absolute 

 exaetness. In one mitosis, 48 chromosomes could clearly be distin- 

 guished, of which number at least 30 were nicely arranged in pairs. 

 The figure 54 was awaited, but rather often a lower number is found. 



Botan. Centralblatt. Band 141. 1919. 18 



