Band 122. Nr. 13. XXXIV. Jahrgang. I. Bd. Nr. 13. 



Botanisches Centralblatt. 



Referirendes Organ 



der 



Association Internationale des Botanistes 

 für das Gesamtgebiet der Botanik. 



Herausgegeben unter der Leitung 

 des Präsidenten: des Vice- Präsidenten : des Secretärs: 



Prof. Dr. E. Warming. Prof. Dr. P. W. Oliver. Dr. J. F. Lotiy, 



und der Redactions-Commissions- Mitglieder : 



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



Prof. Dr. C. Wehmer und Dr. C. H. Ostenfeld. 



von zahlreichen Specialredacteuren in den verschiedenen Ländern. 



Dr. J. P. Lotsy, Chefredacteur. 



No. 13. 



Abonnement für das halbe Jahr 14 Mark 



durch alle Buchhandlungen und Postanstalten. 



1913. 



Alle für die Redaction bestimmten Sendungen sind zu richten an: 

 Redaction des Botanischen Centralblattes, Haarlem (Holland), Spaarne 17. 



Gatin, L., Table chauffante ä temp^rature reglable. (Ann. 

 Inst. Pasteur. XXV. p. 555. 1911.) 



L'instrument preconise par l'auteur remedie aux imperfections 

 des platines chauffantes actuellement en usage; la surface de chauf- 

 fage est considerable; la temperature est la meme sur tous les 

 Points; le reglage s'effectue avec la plus grand facilite. H. Colin. 



Greig-Smith, R., Con tributions to our Knowledge ofSoil- 

 Fertility. N'^ 6. The Inactivity of Soil-Protozoa. (Linn. 

 Soc. N. S. Wales. Abstr. p. II-III. Proc. Nov. 27th 1912.) 



When suspensions of soil-protozoa containing Colpoda cucullus 

 were added to soils previously treated with Chloroform, etc., it was 

 found that the numbers of bacteria were not decreased, and further 

 exaraination showed that the cysts of Colpoda were not destroyed 

 by the volatile desinfectant. Suspensions of amoebae did not induce 

 a diminution of the bacterial increase, and the great augmentation 

 of the bacteria that occurs during the first few days, was shown to 

 occur also when pure cultures of rapidly growing bacteria, such 

 as Bact. putidum, which accompany the amoebae, were added. Ex- 

 periments with unfiltered and cottonwool-filtered suspensions of soil 

 did not show any indication of the activity of the soil-protozoa, 

 from which it is to be inferred that the toxins and nutrients of the 

 soil are alone concerned in the changes that occur in the numbers 

 of bacteria in soils which have been heated or treated with volatile 

 desinfectants. Author's abstract. 



Botan, Centralblatt. Band 122. 1913. 18 



