114 NATURE AND LIFE. 



quantity is smaller, and they are separate. Now, it has 

 lately been discovered that in the latter case, under the 

 influence of light, the green corpuscles we speak of undergo 

 very singular changes of position. Some twelve years ago, 

 Boehm noticed for the first time that in certain unctuous 

 plants the grains of chlorophyll gather at one point of the 

 wall of the cells under the action of the sun. He remarked 

 that the phenomenon does not take place in the dark, nor 

 in the red rays. The flat sheet made up of a single layer 

 of cells, without epidermis, which composes the leaves of 

 mosses, seemed to Famintzin the most suitable for this 

 delicate kind of observations. He followed the movements, 

 that take place in these sheets, by microscopic study. 

 During the day the green coloring-grains are scattered 

 about the upper and lower parts of the leaf-cells. At 

 night, on the contrary, they accumulate toward the lat- 

 eral walls. The blue rays affect them like white light ; 

 the yellow and the red ones keep the chlorophyll in the 

 position it takes at night. The order of activity in the rays 

 seems, then, to differ in this case from that in the phe- 

 nomena of respiration. The researches of Borodine, Pril- 

 lieux, and Roze, proved that these movements of coloring- 

 corpuscles within the cells occur in almost all cryptoga- 

 mous plants, and in a certain number of phanerogamous 

 ones. The lately-published experiments of Roze show 

 that in mosses the grains of chlorophyll are connected by 

 very slender threads of plasma, and may suggest the idea 

 that these threads are the cause of the changes of position 

 just described. Perhaps there is some real relation be- 

 tween them ; but it must not be forgotten that these 

 movements of the plasmatic matter inside the cell take 

 place by day and night, and that light has no marked effect 

 on them. The green particles, on the contrary, creep over 

 the walls of the cell, and move toward the lightest part as 

 zoospores and some infusoria do. 



