386 W. Dörries: Chemische Physiologie 1915 und 1916. [30 



334. Reed, H. S. and Williams, B. The effect of some organic 

 Boil constituents upon nitrogen fixation by Azotobader. (Centrbl. 

 Bakt., II. Abt., XLIII. 1915, p. 166-176.) - Ref. in Bot. Centrbl. CXXXV. 

 1917, p. 329-330. 



335. Sazanoff, W. Versuche über den Einfluss der Phosphat- 

 düngung auf das Wurzelsystem der Zuckerrübe in Russland. 

 (Journ. Opitnoi Agronomü XVI, 1915, p. 140-165.) - Ref. in Bot. Centrbl. 

 CXXXII, 1916, p. 576. • 



336. Schauder, R. und Fischer, W. Zur Physiologie von Phoma 

 betae. (Landw. Jahrb. XL VIII, 1915, p. 717.) - Ref. in Centrbl. Biochem. 

 Biophysik XVIII, 1915/16. p. 648. 



337. Schneidewind, W. u. a. Stickstoff- und Kalidüngungs- 

 versuche aus den Jahren 1911 — 1915. (Arb. D. Landw.-Ges. 283. 



1916, 202 pp.) - Ref. in Bot. Centrbl. CXXXV, 1917, p. 144.^ 



338. Schramm, J. R. A contribution to our knowledge of the 

 relation of certain species of grass-green Algae to elementary 

 nitrogen. (Ann. Missouri Bot. Garden I, 1914, p. 157 — 184.) — Ref. in Bot. 

 Centrbl. CXXXI, 1916. p. 653. 



339. Sehramm, J. R. Some pure culture methods in the Algae. 

 {Ann. Missouri Bot. Garden I. 1914, p. 23-45.) - Ref. in Bot. Centrbl. 

 CXXXI, 1916, p. 654. 



340. Schulze, B. Beitrag zur Frage der Wirkung von Reiz- 

 Btoffen auf die Pflanzenentwicklung. (Landw. Versuchsstat. LXXXVII, 

 1915, p. Iff.) - Ref. in Centrbl. Biochem. Biophysik XVIII, 1915/16, p. 485 

 bis 486. 



341. Schulze, B. Die Düngewirkung des Chlornatriums. 

 (Landw. Versuchsstat. LXXXVI, 1915, p. 323ff.) - Eine indirekte, auf 

 Basenaustausch berulieude Düngewirkung des Chlornatriums findet nicht 

 statt. Für gewisse Pflanzenfamilien ist aber das Natrium als ein die Entwick- 

 lung direkt fördernder Nährstoff anzusehen. 



342. V, Seelhorst, Geilmaiin und Thiele. Untersuchungen über die 

 Kalkempfiudlichkeit der Lupine. (Landw. Presse Nr. 1, 1915.) — 

 Ref. in Centrbl. Bakt.. II. Abt.. XLIV, 1915. p. 411-412. 



343. Shive, John W. A three-salt nutrient Solution for plants. 

 (Amer. Journ. of Bot. II, 1915, p. 157-160.) 



344. Simonini, A. Einwirkung der seltenen Erden auf Bak- 

 terien. II. Mitt. (Centrbl. Bakt., I. Abt.. LXXV, 1915, p. 398-408.) - 

 Ref. in Bot. Centrbl. CXXIX, 1915, p. 470. 



345. Skene, Mac Gregor. The acidity of Sphagnum and its re- 

 lation to chalk and mineral salts. (Ann. of Bot. XXIX, 1915, p. 65 

 bis 87.) — Conclusious: ,,In addition to the criticism and elucidation of various 

 other points. the chief conclusions which may be drawn from the preceeding 

 pages are: 1. There is a Variation in acidity and in sensitiveness to chalk 

 between the different species of Sphagnum. 2. There is a correlation between 

 degree of acidity and degree of sensitiveness. 3. The connexion between the 

 two is indirect, not direct. 4. The Sphagna thrive in acid Solutions: the in- 

 juriouß effect of chalk, and of alkalies in general, is due to the Substitution 

 of an alkaline for an acid reaction. 5. Mineral Solutions are geuerally physio- 

 logically harmless, but may be ecologically harmful. 6. The Sphagna do 



