17 , 6 
Trelease: Salt Requirements of Wheat Plants 
533 
Sachs: 21 NaCl, CaS0 4 , MgS0 4 , Ca 3 (P0 4 ) 2 , KN0 3 . 
Nobbe: 22 KC1, MgS0 4 , KH o P0 4 , Ca(N0 3 ) 2 . 
Tollens: 23 NaCl, MgS0 4 , KH.PO.*, KNO s , Ca(N0 3 ) 2 . 
Schimper: 24 NaCl, MgS0 4 , K 2 HP0 4 , KN0 3 , Ca(N0 3 ) 2 . 
Detmer: 25 KC1, MgS0 4 , KH„P0 4 , Ca(NO s )„. 
Pfeffer : 26 KC1, MgS0 4 , KH 2 P0 4 , KN0 3 , Ca(N0 3 ) 2 . 
Hartwell, Wheeler, and Pember: 27 KC1, MgS0 4 , Ca(N0 3 ) 2 , 
Ca(H 2 P0 4 ) 2 . 
Stile's: 28 NaCl, MgS0 4 , KH 2 P0 4 , KN0 3 , CaS0 4 . 
Brenchley: 29 NaCl, MgS0 4 , KH 2 P0 4 , KNO a , CaS0 4 . 
On the other hand, very few nutrient solutions without a 
chloride have been recommended for plant cultures. Of this 
smaller group the following are familiar examples: 
Knop (Tottingham) : 80 MgS0 4 , KH 2 P0 4 , KN0 3 , Ca(N0 8 ) 2 . 
21 Sachs, J., Bericht fiber die physiologische Thatigkeit an der Versuchs- 
station in Tharandt. IV. Vegetations-Versuche mit Ausschlus des Bodens 
fiber die Nahrstoffe und sonstigen Ernahrungsbedingungen von Mais, 
Bohnen und anderen Pflanzen, Landw. Versuchsst. 2 (1860) 219-268. 
22 Nobbe, F., Ueber die physiologische Function des Chlor in der Pflanze, 
Landw. Versuchsst. 7 (1865) 371-386. 
23 Tollens, B., Ueber einige Erleichterungen bei der Cultur von Pflanzen 
in wasserigen Losungen, Journ. Landw. 30 (1882) 537-540. 
M Schimper, A. F. W., Zur Frage der Assimilation der Mineralsalze 
durch die grtine Pflanze, Flora 73 (1890) 207-261. 
25 Detmer, W., Practical plant physiology. Translated by S. A. Moor. 
London (1898) 2. 
26 Pfeffer, W., The physiology of plants. Translated by A. J. Ewart. 
Oxford 1 (1900) 420. 
27 Hartwell, B. F.; Wheeler, H. J.; and Pember, F. R.; The effect of the 
addition of sodium to deficient amounts of potassium upon the growth of 
plants in both water and sand cultures, Rhode Island Agric. Exp. Sta. Ann. 
Rep. 20 (1907) 299-357. 
28 Stiles, W., On the relation between the concentration of the nutrient 
solution and the rate of growth of plants in water culture, Ann. Bot. 29 
(1915) 89-96. 
29 Brenchley, W. E., The effect of the concentration of the nutrient solu- 
tion on the growth of barley and wheat in water cultures, Ann. Bot. 30 
(1916) 77-90. 
60 Knop, W., Quantitativ-analytische Arbeiten fiber den Ernahrungs- 
process der Pflanzen. II. Landw. Versuchsst. 4 (1862) 173-187. Totting- 
ham, W. E., A quantitative chemical and physiological study of nutrient 
solutions for plant cultures, Physiol. Res. 1 (1914) 133-245. 
