630 EXPEKIMENT STATION RECORD. 



transpiration stream does not exert an accelerating effect on the entrance of 

 salts. 



Influence of the salts common in alkali soils upon the growth of rice 

 plant, I-IV, K. MiYAKE {Bot. Mag. [Tokyo], 27 (1913), Nos. 321, pp. 118-182; 

 322, pp. 193-204; 323, pp. 224-233; 324, PP- 268-270).— The author carried out 

 a number of tests regarding the influence upon the growth of young rice 

 seedlings exerted by chlorids, nitrates, sulphates, and carbonates of sodium, 

 calcium, magnesium, and potassium usually found in alkali soils, the conclu- 

 sions from which may be summarized as follows : 



The alkali and related salts, tested singly, proved to be toxic or stimulating 

 according to concentration, each having its maximal points ; but tested in com- 

 bination with each other, their toxic effects may decrease or even disappear, 

 in some cases given the antagonistic action of salts (otherwise toxic to the 

 plant) for each other being ascribed to the influences of the ions present 

 owing to the dissociation of the salts. The curve of antagonism between sodium 

 and potassium salts shows two maxima. 



Mutation in Penicillium glaucum and Aspergillus niger under the action 

 of known factors, H. J. Waterman {K. Akad. Wetensch. Amsterdam, Proc. 

 Sect. Sci., 15 {1912), pt. 1, pp. i2-^-i28).— Studies carried out with cultures 

 of P. glaucum showed that this fungus exhibits mutations when cultivated in 

 the presence of any one of several acids tested, as evidenced by differences 

 in odor, tenacity, number of spores, etc. Experiments with A. niger showed 

 enormous dift^erences in metabolism of three strains obtained. It is claimed 

 that by the methods employed it is possible to show the existence of mutations 

 even when visible external differences between the cultures are lacking. 



Action of hydrogen ions, boric acid, copper, manganese, zinc, and 

 rubidium on the metabolism of Aspergillus niger, H. J. Waterman (K. 

 Akad. Wetmisch. Amsterdam, Proc. Sect. Sci., 15 (1912), i)t. 1, pp. 153-764).— 

 Reporting the results of studies on metabolism, the author states that mutation 

 was again apparent in the behavior of A. niger in cultures containing one or 

 more of these components. Metabolism was but little or not at all influenced 

 by addition of sulphuric acid or zinc and copper salts (the latter counteracting 

 spore formation). Manganese acted favorably on the rapidity of spore forma- 

 tion. Rubidium, substituted for potassium, reduced spore formation but in- 

 creased mold weight. This action is not considered as necessarily favorable, 

 as in certain concentrations of copper sulphate, zinc chlorid, and zinc sulphate, 

 a resulting increase of weight is inversely proportional to spore formation. 



Relations of lipoids to differences in the electrical potential in plant 

 organs, J. Loeb and R. Beutnee (Biochem. Ztschr., 51 {1913), No. //, pp. 288- 

 299). — The authors summarize the conclusions reached as the result of this 

 study, in the claim that differences of potential noted in certain living plant 

 organs are determined by the presence of a superficial layer of phosphatids or 

 of allied substances not readily soluble in water. Variations in the characters 

 of these, as regards their solvents, are related to the electrical differences noted. 

 Influence of anesthetics on supeirficial differences of electrical potential in 

 plant and animal tissues, J. Loeb and R. Beutner {Biochem. Ztschr., 51 

 {1913), No. 4, pp. 300-306). — Claiming to have shown, in previous communica- 

 tions cited, that the differences of potential observable between unwounded 

 surfaces of plant organs and aqueous solutions of salts, present sharply defined 

 and reversible alterations with differences in concentration of the latter, also 

 that nonelectrolytes, as sugar and urea, show no such behavior, the authors 

 report results of further study regarding the influence of several anesthetics, 

 etc., in connection with constant concentration as regards the salt content, 

 employing therein leaves of rubber plant or apple and muscles of the frog. 



