Contributions to the Chemistry of Chlorophyll. 315 



be easily distinguished from chlorophyll, and which give it the 

 character of a substance sui generis. I would propose to call it, until 

 a better name can be found, alkachlorophyll, a name pointing at the 

 same time to the agent by which it is formed and to its resemblance 

 to the mother substance. It shows no signs whatever of crystalline 

 structure, is quite insoluble in boiling water, but easily soluble in 

 alcohol, ether, chloroform, benzol, aniline, and carbon disulphide, but 

 insoluble in petroleum ether. Its solutions have a brilliant green 

 colour with a pronounced bluish tinge, by which they may be easily 

 distinguished from ordinary chlorophyll solutions, and a marked red 

 fluorescence. Tho ethereal solution shows no less than six absorption 

 bands. Of these, the two in the red probably correspond with those 

 first observed by Chautard, while the one in the blue is in a part of 

 the spectrum in which total absorption, takes place with ordinary 

 chlorophyll solutions. 



Alkachlorophyll in solution shows a remarkable degree of per- 

 manence when exposed to the combined action of air and light as 

 compared with; chlorophyll. Having prepared an ethereal solution of 

 alkachlorophyll, and also an ethereal solution of ordinary chlorophyll,, 

 from fern fronds, as nearly as possible of the same depth of colour as 

 the difference of tint would permit, I exposed the two solutions in 

 loosely stoppered bottles to the action of alternate sunlight and 

 diffused daylight in a window facing the south. The experiment 

 commenced on the 21st February. On the 27th of the same month 

 the chlorophyll solution had lost its green colour and become yellow, 

 the chlorophyll bands having disappeared, those still remaining being 

 due to phyllocyanin, the formation of which was doubtless due to de- 

 composition of part of the chlorophyll. The solution of alkachloro- 

 phyll, on the other hand, was still green, and still showed the six 

 original bands, though it was found to have lost in intensity of colour 

 when compared with another portion of the same solution that had 

 been kept in the dark. On the llth March the solution had become 

 pale green, and now only showed four bands. On the 25th March 

 the solution still showed the bands in the red and blue, though they 

 appeared very faint. On the 8th May a slight green tinge was still 

 visible, but the bands had nearly disappeared. The relatively great 

 stability of alkachlorophyll when exposed to air and light is of itself 

 sufficient to prove that by the action of alkali chlorophyll undergoes a 

 thorough change. 



The action of acids on alkachlorophyll is especially interesting, be- 

 cause the products to which it gives rise differ entirely from those 

 derived from the decomposition of chlorophyll with acids. When 

 acetic acid is added to an alcoholic solution of alkachlorophyll the 

 solution on heating loses its green colour, which changes to a dirty 

 purple. The substance is now completely decomposed, but no phyllo- 



