114 JOUENAL OF THE MiTCHELL SoCIETY [April 



ence of certain Phases of Taxonomy, Professor Aven ISTelson. 

 said:^ 



We are on the eve of a new era of reconstruction. Already the pendu- 

 lum is swinging back toward greater conservatism. The dismemberment 

 of genera and the multiplication of species proceed more cautiously. 

 This grows out of the revitalized aim, "Make it easier for others to 

 know plants." 



The perplexity of the systematist may be understood when we 

 consider the increasing evidence of numerous distinct strains 

 within " species " whose characteristics are inherited and ap- 

 parently well fixed. Such strains were reported by Mr. Chas. 

 A. Shull in the cockle-burr, Xanthium canadense, and Profes- 

 sor A. F. Blakeslee showed that in cultures from a single spore 

 of a species of Mucor variation occurred that retained their 

 characters for some time. Of their variation he says " Many of 

 them would undoubtedly be described as distinct species in the 

 group." 



Experiments by Mr. Jacob R. Schramer with seven species 

 of green algse gave no evidence of any power to fix free nitro- 

 gen. 



Professor W. J. V. Osterhout reported as follows r'^ 



Van't Hoff's formulation of the laws of chemical dynamics has proved 

 so stimulating to various lields of chemistry that it may be expected to be 

 similarly useful if it can be applied to the activities of living protoplasm. 

 The writer linds that by measuring the electrical resistance of living tissues 

 it is possible to follow the progress of reaction in protoplasm in the 

 same way that Van't Hoff followed the progress of reactions in vitro. It 

 therefore becomes possible to apply Van't Hoff's methods and formulae 

 directly to protoplasm in its living and active condition. 



Professor Osterhout also finds that by means of electrical 

 measurements of living tisues it is possible to predict which 

 salts will antagonize each other when allowed to act upon these 

 tissues. 



Dr. R. H. True advocated the use of '' normal physiological 

 solution " for experimental purposes, rather than distilled 

 water, which cannot, in practice, be obtained pure, and which 

 moreover has been found to be injurious to certain plants, prob- 

 ably by absorbing from their roots some of the constituents 

 necessary to the maintainance of life activities. 



5 Science N. S. .39 : 255. Feb. 13, 1914. 

 « Science N. S. 39 : 292. Feb. 20, 1914. 



