pringsiieim's reskarches on chlorophyll. 81 



niixtuie depends upon the modified chlorophyll, for the 

 move highly-developed crysta,lloidnl processes, if exposed for 

 a short time to light, change colour and get lighter, often 

 bleaching slowly from the point backwards, and in this way 

 may become quite colourless (fig. 7j. The crystal-like pro- 

 jections and the short rods are often from the first destitute 

 of colour. 



It is that constituent of these extruded masses which forms 

 the crystalloidal bodies, or rathei the form in which it pre- 

 exists in the chlorophyll-corpuscle, that is termed hypochlorin. 

 Is it an independent constituent of the chlorophyll-corpuscle, 

 or is it derived from the green colouring matter by the 

 action of the acid ? 



Were it a product of the action of the acid on the green 

 colouring niatter its presence should be indicated in every 

 chloropiiyll-corpuscle when treated with the acid, for there 

 is no reason to doubt that the characters of the chlorophyll- 

 corpuscles in a normal tissue, in one and the same cell at 

 least, are essentially alike. But this is by no means the 

 case. Often the crystalloid-bodies develope only upon a few 

 chlorophyll-corpuscles in a cell (fig. 7), and are absent from 

 the others, or they may be entirely absent from one or more 

 cells in a tissue otherwise rich in the substance. Again, in 

 the majority of Algce where the chlorophyll is attached to 

 masses of various forms, whilst hypochlorin is rarely entirely 

 absent from a cell or from a filament, the amount present 

 varies much both with the season and with the stage of 

 development of the cells. 



This sporadic distribution cf the hypochlorin, while it indi- 

 cates the existence of this substance as a general con- 

 stituent of the chlorophyll-corpuscles, independent of the 

 colouring matter, points also to its function as a formative 

 material, like starch and oil, in the chlorophyll-corpuscle, and 

 its detection will depend upon whether it has accumulated 

 or been used up in the chlorophyll-corpuscle; the amount 

 discoverable at any time representing excess of supply over 

 demand at that particular moment. 



In plants with chlorophyll-bands or plates, further evi- 

 dence of the presence of hypochlorin as a distinct and inde- 

 pendent body is aff"orded by definite anatomical relationships 

 of the crystalloid outgrowths to the chlorophyll-masses. 

 In Spirogyra, for example, they appear at widely and almost 

 equally distant points on the edge or middle line of the 

 bands (tig. 10). The same is observed in those CEdogoniem 

 that possess chlorophyll-bands, and in Draparnaldia the 

 crystalloids, always few in number, occur on the crossing 



VOL. XXII. MEW SER. If 



