. 
ie) 
19. 
20, 
Hoyt: CULTURES OF SPIROGYRA 359 
LITERATURE CITED 
Benecke, W. Ueber die Giftwirkung verschiedener Salze auf 
Spirogyra, und ihre Entgiftigung durch Calciumsalze. Ber. 
Deuts. Bot. Ges. 25: 322-337. 1907. 
Bokorny, Th. Ueber den Einfluss des Calciums und Magnesiums 
auf die Ausbildung der Zellorgane. Bot. Centralbl. 62: 1-4. 
1895. 
Bokorny, Th. Nochmals iiber die Wirkung stark verdiinnter 
Lésungen auf lebende Zellen. Arch. Ges. Physiol. 110: 174- 
226. 
1905. 
. Breazeale, J. F. Effect of the concentration of the nutrient solu- 
tion upon wheat cultures. Science II. 22: 146-149. 1905. 
. Breazeale, J. F. Effect of certain solids upon the growth of seed- 
lings in water cultures. Bot. Gaz. 41: 54-63. 1906. 
Bullot, G. On the toxicity of distilled water for the freshwater 
Gammarus. Univ. Calif. Publ. Physiol. 1: 199-217. 1904. 
Dandeno, J. B. - The relation of mass action and physical affinity 
to toxicity. Amer. Jour. Sci. IV. 17: 437-458. 1904. 
Deherain, P. P. & Demoussy, E. Sur la germination dans l’eau 
distillée. Compt. Rend. 132: 523-527. 1901. 
Jensen, G. H. Toxic limits and stimulation effects of some salts 
and poisons on wheat. Bot. Gaz. 43: 11-44. 1907- 
sc latnr Ernst. Kultur der Mikroorganismen. Leipzig. 1907. 
Livingston, B. E., Britton, J. C. & Reid, F. R. Studies on the 
properties of an unproductive soil. U. S. Dept. Agric., Bur. 
Soils, Bull. 28. 1905. 
Livingston, B.E. Further studies on the properties of unproductive 
soils. U.S. Dept. Agric., Bur. Soils, Bull. 36. 1907. 
Loeb, J. Studies in general physiology. Chicago. 1905. 
Loeb, J. The dynamics of living matter. New York. 1906. 
Loew, O. The physiological réle of mineral nutrients in plants. 
U. S. Dept. Agric., Bur. Plant Ind., Bull. 45. 1903. 
Loew, O. Note on balanced solutions. Bot. Gaz. 46: 302, 303. 
Eoew, O. Bull. Col. Agric. Tokio 7: 7- 1906 (quoted verbatim 
by Benecke, Ber. Deuts. Bot. Ges. 25: 324- 1907). 
Loew, O. & May, D. W. The relation of lime and magnesia to 
plant growth. U.S. Dept. Agric., Bur. Plant Ind., Bull. I. 1901. 
Lyon, E. P. A biological examination of distilled water. Biol. Bull. 
6: 198-202. 1904. 
Nageli, C. von. Ueber oligodynamische Erecheinungen in lebenden 
Zellen. Neue Denkschr. Schweiz. Gesell. Naturforsch. (Nouv. 
