Physiologie. 563 



great variety of Solutions. The purpose of this paper is not to give 

 the results of these experiments but merely to State some general 

 principles in the hope that they may be of use to those who have 

 occasion to make quantitative studies on antagonism. 



As the Solutions become more dilute, the antagonism curve 

 becomes flatter, and it is evident that at still greater dilutions it 

 must tend to become a horizontal straight line. 



The author constructed a solid model which gives a complete 

 description of the changes in growth produced by diluting the various 

 mixtures. 



When dilute Solutions are employed, the maximum growth ob- 

 tained in a fully balanced Solution may be greater than that in 

 distilled water, owing to the nutrient action of the Solution. But 

 when strong Solutions are employed, this is not the case, for the 

 osmotic pressure of the strong balanced Solution will inhibit growth. 



In general. growth in strong Solutions furnishes a much more 

 satisfactory criterion of antagonism than growth in weak Solutions. 

 The Inhibition of growth due to the osmotic pressure of the strong 

 Solutions does not noticeably affect the form of the antagonism 

 curve, since it makes itself feit in the pure Solutions to about the 

 same degree as in the mixtures. When we employ the method of 

 mixing equally toxic Solutions, the osmotic disturbances are com- 

 pensated in a manner which has been previously discussed by the 

 author. Jongmans. 



Osterhout, W. J. V., The raeasurement of antagonism. 

 (Bot. Gazette. LVIII. p. 272—273. 3 Text Fig. 1914.) 



The author summarizes his' results as foUows: 



The measurement of antagonism in Solutions containing more 

 than two components presents no difficulty as long as we pursue 

 the method of mixing equally toxic pure Solutions. 



Methods are suggested for the graphical expression of antago- 

 nism in mixtures of three or more components. Jongmans. 



Poisson , J., Germination apres un long en fouissemen t 

 de graines du Chenopodium Botrxs. CBull. Soc. bot. France. LX. 

 p. 518—520. 1913.) 



A la suite de fouilles pratiquees dans un point d'un domaine, 

 on avait remarque qu'une plante qui jusqu'alors n'avait pas ete vue 

 dans la region, etait apparue en quantite. L'auteur l'a determinee 

 comme Chenopodium Botrys. On estime qu'il y a cinq ou six cents 

 ans que ce Chenopodium a ete enterre plus qu'il ne fallait pour que 

 ses graines se missent ä germer. Jongmans. 



Rose, E., Energie assimilatrice chez les plantes culti- 

 vees sous differents eclairemen ts. (Ann. Scienc. nat. 9. 

 Bot. XVII. p. 1 — 110. 44 Fig. 1913.) 



Les conclusions generales de ce travail sont les suivantes. 



L'ensemble des experiences faites avec detail sur deux plantes 

 prises comme types a donne des resultats qui sont certainement 

 susceptibles d'une certaine generalisation. Ces resultats montrent 

 que les differentes especes vegetales ä chlorophylle doivent presenter 



