282 W. Wen dl er: Chemische Physiologie 1917— 1919 [26- 



electrolytes. 3. Tlie filtrate from the precipitation with (NHO2SO», when 

 dialyzed until free from sulphates, is not toxic to the root hairs of Tradescantia 

 cuttings. 4. Bog water, when dialyzed for the same length of time as this fil- 

 trate, is toxic to these root hairs. 5. The distillate from bog water gives no 

 precipitate with eleetrolytes, is much less acid than bog water, and is not toxic 

 to these root hairs. 6. The concentrate obtained when bog water is distilled 

 to approximately one-sixth of its original volume gives a lieavier precipitate 

 with electrolytes than does bog water. It is also more acid and more toxic to 

 these root hairs. 7. The residue from complete evaporation of bog water is 

 a brownish powder which is soluble in cold water, insoluble in aleohol and 

 gasoline, and practically insoluble in ether. 8. This water Solution of the 

 residue is toxic to the root hairs of Tradescantia. 9. No solid matter was 

 tlirown out of bog water by centrifuging. 10. Chemical analyses of P u g e t 

 S o u n d bog waters give results similar to those reported for other American 

 bog waters. 11. The toxicity of bog water to Tradescantia cuttings seem to be 

 connected with the matter in it that is in a colloidal state. 12. The oxidation 

 of this toxic matter to non-toxic matter seems to be a basis of agricultural 

 practice in beginning bog lands into cultivation." 



2(14. Rüssel, E. I. The n a t u r e a n d the a m o unl o 1 t ii e 

 fluetuations in n i t r a t e Contents o f a r a b 1 e s o i 1. ( Journ. 

 Agric. Sei. 1914, 6, p. 18 — 57.) — Siehe ,, Allgemeine Pflanzengeographie 1914 

 1914—1921", Nr. 372. 



205. Rüssel, E. I. and Applegard, A. Theatmosphereofthesoil. 

 (Journ. Agric. Sei. 1915, 7, p. 1 — 48.) — Siehe „Allgemeine Pflanzengeographie 

 1014—1921 , Nr. 372. 



206. Rüssel, E. I. S o i 1 conditions a n d p 1 a n t gro w t h. Third 

 edition. London (Longmans, Green and Co.) 1917, VIII u. 243 pp. — Siehe 

 „Allgemeine Pflanzengeographie 1914—1921" Nr, 373. 



21)1. Rüssel, E. J. and Applegard, A. The i n f 1 u e n c e o f s o i 1 con- 

 ditions o n t h e decoraposition oforganic matter in t Ii e soll. 

 (Journ. Agric. Sei. 191(3/17, 8, p. 385.) — Siehe „Allgemeine Pflanzengeogra- 

 phie 1914—1921", Nr. 374. 



208. Rüssel, E. J. and Richards, E. H. The washing out of 

 n i t r a t e s b y d r a i n a g e w a t e r f r o m u n c r o p p e d a n d u n - 

 m a n u r e d 1 a n d. (Journ. Agric Sei. X, 1919, p. 22 — 43.) 



209. Salisbury, E. I. T h e significance of the calcicolous 

 habit. (Journ. of Ecology 1920, 8. p. 202—215.) — Siehe „Allgemeine 

 Pflanzengeographie 1914 — 1921", Nr. 379. 



210. Shorey, Edmund C, Ery, William, H. and Hazen. William. C a 1 - 

 c i u m c o m p o u n d s in s o i 1 s. (Journ. Agric. Res. 8, 1917, p. 57 — 77.) 



From the analytical data the quantities of calcium carbonate, calcium 

 sulphate, calcium combined with humus Compounds, and calcium present as 

 easily and difficultly decomposable Silicates have been calculated. 



211. Spurway, C. H. S o i 1 a c i d i t y and the h y d r o 1 y t i c 

 ratio in s o i 1 s. (Journ. Agric. Res. 11, 1917, p. 659—672.) 



212. Stewart, Guy R. Effect of season and c r o p g r o w t h 

 in modifying the soil extra ct. (Journ. Agric. Res. 12, 1918,. 

 p. 311—368, mit 1 Tai.) Summary: „1. The water-soluble nutrients in 

 13 soils, of two different types, have been periodically determined durmg 

 (wo seasons. 2. Throughout the second season comparisons Avere made botween 



