720 EXPERIMENT STATION RECORD. 



physiological function in tlie nutrition of the green plant wbich is regulated by 

 the plant itself. Plants utilize chlorophyll as a sensibilizer by which they 

 adapt their chlorophyll apparatus to the environment in which they grow. 



An extended bibliography is appended to the article. 



The action of light on chlorophyll, P. A. Dangeard {Compt. Rend. Acad. 

 Sci. [Pari-^l. 131 (WIO). No. 26, pp. J.3S6-/,9SS) .—Attention is called to the effect 

 of light upon an alcoholic solution of chlorophyll. By means of a simple con- 

 trivance the author was able to expose the solution to a pure spectrum for a 

 period of 8 days, and the decoloration took place immediately in that^ part of 

 the spectrum which corresponds to the principal absorption band of chlorophyll, 

 followed later by bleaching in the neighboring regions which correspond to the 

 other absorption bands. The chlorophyll was not decolored in the other por- 

 tions of the spectrum, although it I'emained for 8 days subject to the effect of 

 light. 



The action of different colored light on plants, C. Flammarion {Bui. Mens. 

 Off. Rcnsciff. Agr. [Paris;]. 9 (1910), No. 11, pp. 126 1-126 Ji).— In continuation of 

 investigations begun by the author in 1894, a report is given on the observa- 

 tions carried on during the past 2 years on the effect of different colored light, 

 on the translocation of albuminoids (E. S. R., 22. p. 529). The first year's 

 results, in which it appeared that a greater increase in nitrogen took place 

 under the colored than under the clear glass and that this increase was greater 

 under those colors which least stimulated chlorophyll production, have been 

 confirmed by subsequent investigations. 



In connection with these studies some observations were made upon chrysan- 

 themums in which plants grown under different colored screens were found to 

 behave v£ry differently in relation to the size, form, and color of their flowers. 



Experiments on the fall and renewal of leaves, C. Flammarion {Bui. Mens. 

 Off. Rcnscig. Agr. [Paris], 9 {1910), No. 11, pp. 1272-1273) .—In experiments 

 begun in 1891, the author by means of different colored screens has undertaken 

 to influence the fall and renewal of leaves of one of the common oaks. The 

 plants were grown in pots, and by means of protection from freezing he has 

 been successful in developing a form of the oak which does not lose its leaves 

 in autumn, the new leaves being put out prior to the fall of the old ones. The 

 persistence of the leaves is especially noted under certain illuminations. 



Influence of temperature on the phenomena of growth, J. Loisel {Bui. 

 Mens. Off. Renseig. Agr. [Paris], 9 {1910), No. 11, pp. 1267-1272).— The author 

 reviews some of the theories relative to the temperature requirements of plants 

 and presents data on the period of leafing and flower hig of a number of species 

 preliminary to an extended study of the relation between temperature duration 

 and phases of development of plants. 



The induced maturity of seeds, P. Mxzt (Cornpt. Rend. Acad. Sci. [Paris], 

 151 {1910). No. 26, pp. 1383-1386) .—The author states that seeds of maize or 

 peas taken from the ear or from the pod at a time when they contain from 50 

 to 60 per cent of water will not germinate under conditions favorable to plant 

 growth, but that if dried in the air for several days they will germinate and 

 give rise to normal plants. 



In considering the reason for this, 3 theories are propounded, (1) that there 

 is an oxidation of material in the seed which is capable of maintaining the 

 embryo in a latent stage. (2) that a chemical condensation takes place which 

 modifies the composition of the cell sap, and (.3) that there is an evaiwration 

 of the volatile material in the seed that would tend to retard the growth of 

 the embryo. The third theory is considered the most possible one, and the 

 author shows that seeds which contain a considerable proportion of ethyl 

 aldehyde in the fresh state lose this upon drying, and further that dry seeds 



