84 Morphologie, Teratologie, Befruchtung, Cytologie. 



thus becomes the centre of a separate osmotio System. No evidence 

 was found in support of the view that the contraction of the atta- 

 ched fibrils draws the daughter chromosomes to the poles of the 

 spindle. Such fibrils may serve as guide lines, but take no active 

 part in the movement. The spindle is regarded simply as an ex- 

 pression of a State of tension in the cytoplasm, this tension being 

 caused, in the first place, by nuclear osmotic changes. 



Agnes Arber (Cambridge). 



Salisbury, E. J.. Polymorphism in the flower of Silene ma- 

 ritima. (New Phyt. XI. N" 1. p. 7—12. 1 pl. and 1 fig. 1912.) 



The author has studied Silene maritima at Blakeney Point 

 in Norfolk. Great variety is observable among the flowers. The 

 author concludes that six definite forms can be distinguished, and 

 to these he assigns names. Agnes Arber (Cambridge). 



Spratt. E. R.. The Morphology of the Root Tuber des ol 

 Abius and Eleagnus, and the Polymorphism of the Orga- 

 nism causing their Formation. (Ann. Bot. XXVI. No. 101. 

 p. 119—127. Jan. 1912.) 



The root tubercles of Abius and Eleagnus are modified lateral 

 roots. Cultures were made to attempt to isolate bacteria from their 

 internal tissues, with the result that Pseudomonas radicicola was 

 demonstrated to be present and to be the cause of the developmeni 

 of the nodule. In Eleagnus the bacteria occur mainly in the region 

 immediately behind the growing point, while in Alnus the bacte- 

 roidal tissue traverses the vvhole length of the nodule. 



Pseudomonas radicicola is a Polymorphie organism , appearing 

 in the form of bacillus and coccus. The more resistant coccus form 

 appears to be correlated with scarcity of available carbohydrate and 

 change of environment. It is stated that the organism is capable of 

 fixing atmospheric nitrogen when isolated from the tubercles. and 

 that'its presence is undoubtedly beneficial to the plant. 



W. E. Brenchley. 



Sylven, N., Nagra monströsa t'ormer a( Anemone pratensis 

 L. (Svensk Botanisk Tidskrift. VI. p. 218—228. 6 Textfig. 1912. 

 Deutsches Resume.) 



Aus der Insel Oeland werden vom Verf. zwölf monströse For- 

 men von Anemone pratensis beschrieben und grösstenteils abgebildet. 



1. Mit vergrösserten , m. o. w. zusammengewachsenen Kelch- 

 blättern. — 2. Mit schwacher \'ermehrung der Kelchblätter. — 3. 

 Wie 2, äussere Kelchblätter gelappt. — 4. Kelchblätter stärker ver- 

 mehrt (bis auf 20-30), die äusseren in feine, grünviolette Zipfel 

 zerschlitzt, die inneren kronblattähnlich, bisweilen an der Spitze 

 gelappt. Involucralblättcr durch Spaltung stark vermehrt. An einer 

 ungestielten Blüte gingen diese fast unmerklich in die Blumenblätter 

 über. — 5. Wie 4, mit sehr stark vermehrten und zerschlitzten 

 Kelchblättern; Staubblätter petaloid, oft zerschlitzt. — 6. Kelch- und 

 Staubblätter stark vermehrt, noch mehr vergrUnt und involucral- 

 blattähnlich. Bisweilen doppelte Quirle von Involucralblättern. — 

 7. Reichliche Vermehrung und vollständige Vergrünung der Kelch- 

 und Staubblätter. — 8. Wie 7, aber die Blüten ungestielt. — 9. 



