222 EXPERIMENT STATION RECORD. 



coloration, the foniun-liou iiiuiarcnlly bein.y; throu^'h the albuminoid rontont of 

 the leaves. An exaniiuatiou of a number of species showed that in some the 

 quantity or ratio of the albuminoids of tlie leaf remains permanent from July 

 until the time when the chlorophyll begins to disappear, while in others tlie 

 ratio becomes gradually and permanently less with the advance of the season. 



In general those leaves in which there is a marked reduction in the albu- 

 minoid content become red in autumn, while those in which the albuminoid 

 content remains nearly constant are brown. Some exceptions are noted to 

 this, particularly in the leaves of oak and beech, which are occasionally bright 

 red, and this is explained by different physiological activity, there being a 

 transfer of the albuminoid due to the prolonged vegetation of the tree. The 

 relation between the red coloring and the albuminoid content suggests that 

 there is probably a connection between the diminution of the albuminoid matter 

 and the development of the vivid crimson or purple coloration. 



The influence of acidity on germination, Mile. G. Promsy {Compt. Rend. 

 Acad. Set. [Paris], 152 {1911), No. S, irp. .'iBO-.'iB^; ahs. in Rev. 8cl. [Paris], Ji9 

 (1911), I, No. 9, p. 282). — The author found that different acids not only in- 

 creased the growth of various plants, some more rapidly than others, but also 

 stimulated a greater production of dry matter, when determined at the end of 

 germination after the plants had become green. 



The organic acids, of which there were a number, are held to contribute to 

 the nutrition of the plants. Germination was accelerated in proportion to the 

 different organic acids used and the species of plant experimented upon. The 

 author claims that the favorable action often attributed to bases can not be 

 considered as due to the neutralization of the acid of the plant. 



The use of solutions of potash to determine the germinative faculty of 

 seeds, P. Lesage (Compt. Rend. Acad. 8ci. [Paris], 152 (1911), No. 10, pp. 

 615-617). — The author describes a method for determining the germinative 

 ability of seeds by placing them in solutions of caustic potash. Varying dilu- 

 tions of a normal solution were used, and for different kinds of seed it was 

 found that the strength of solution had to be varied. 



Nonviable seed was found to discolor the solution within a few hours, while 

 sound viable seed did not. This method was worked out for the seeds of cress, 

 but it has been tested on a number of other kinds of seed and found to apply to 

 many of them. 



The effect of the activation of the atmosphere by radium emanations on 

 the germination and growth of plants, G. Fabke (Compt. Rend. Soc. Biol. 

 [Paris], 70 (1911), No. 6, pp. 187, i88).— The author reports the effect of 

 radium emanations on the germination and development of Sterigmatocijstis 

 nigra, Mucor mucedo, and Linum cat liar ticum. 



With Sterigmatocystis the germination of the spores on acid gelatin was re- 

 tarded by the emanation of radium of high potency. The optimum dose of one-half 

 microcurie per cubic centimeter of air retarded germination for the first three 

 days, but on the fourth day the growth equaled that of check cultures. With 

 a double quantity the germination was greatly reduced and the growth of the 

 mycelium was retarded. Similar results were obtained with Mucor. 



The germination of seeds and development of the seedlings of Linum were 

 favored by increasing emanations up to 1.5 microcuries for 2 liters of air. The 

 growth was retarded by increasing the amount of emanation, and germination 

 ' w^as retarded where it amounted to 40 microcuries per liter of air. 



Nitrogen and chlorophyll in galls and etiolated leaves, M. Molliaed 

 (Compt. Rend. Acad. Sci. [Paris], 152 (1911), No. 5, pp. 274-277).— A study 

 is reported of the nitrogen content of normal leaves and of galls formed by 

 various insect parasites on a number of species of plants, in which it was found 



