32 Livingston : Chemical stimulation of a green alga 



nomenon of adsorption known to soil physicists for some time,* 

 but only now applied to the study of toxicity of salts. It 

 appears from Dandeno's paper that even the walls of the vessel in 

 which a water culture is grown may exert an appreciable influence 

 in this way, thus decreasing the stimulating power of a solution. 

 It is well to call attention here also to three papers in the 

 same field in animal physiology. The influence of poison salts 

 upon fishes was studied by Kahlenberg and Mehl t and determin- 

 ation made of the killing concentrations. As their results show, 

 these authors were working largely with the toxic effect of the 

 solutions upon the delicate vascular membranes of the gills. 

 Kahlenberg % also made a study of the relation of taste to acidity, 

 in salts and acids. But by far the best and most satisfactory 

 paper which has appeared from the animal side, and in many ways 

 from the standpoint of all general physiology, is that of Mathews § 

 who carefully determined for a large number of salts, the concen- 

 trations necessary to inhibit the development of eggs of the fish, 

 Fundulits heteroclitus. His paper will be 



a little farther on. 



The effect of one salt or ion in counteracting that of another, 

 when these are in a mixed solution is a very important topic in 

 connection with the general subject of stimulation, K 

 Paul, II Clark,^ Kearney and Cameron,^ 



some 



■^ T" ' ' ' 



True,tt ^"d True and 

 Gies,§§ and others have investigated this question with interesting 

 result which cannot be even touched upon here. 



*See Briggs, L. J. The mechanics of soil moisture. U. S. Dept. Agric. Div. 

 of Soils, Bull. No. lo. 1897. — Investigations on the properties of soils. U. S. 

 Dept. Agric. Field Operations Div. Soils, 1900: 415-421, 1901. 



I Kahlenberg, L. & Mehl, H. F. Toxic action of electrolytes upon fishes. Jour. 

 Phys. Chem. 5: 113-132. 1901. 



:|: Kahlenberg, L, The relation of the taste of acid salts to their degree of dis- 

 sociation. Jour. Phys. Chem. 4: 533-537. 1900. 



§ Mathews, A, P. The relation between solution tension, atomic volume, and 

 the physiological action of the elements. Am. Jour. Physiol. 10 : 290-323. 1904- 

 See also his previous paper on nerve irritability, Science IL 17 : 728-733. 19^3* 



jl Kronig, B. & Paul, T. Zeitschr. filr Hygiene u. Infect. 25 : I-112. 1897- 



^Clark, J. F. Jour. Phys. Chem. 5: 289-316, 1901. 

 ** Kearney, T. H. and Cameron^ F. K. U. S. Dept. Agric. Report No. 7^- 



1902. 



ft True, R. H. Am. Jour, Sci. IV. 9: 183-192. I900. 



^gTrue, R. H. & Gies, \V. J. Bull. Torrey Club 30 : 390-402. 1903. 



