312 Mr. E. Schunck. 



stances the properties of which closely resemble those of phyllo- 

 xanthin. One of these is Pringsheim's " hypechlorin." After im- 

 mersing tissues containing chlorophyll in dilute hydrochloric acid, 

 Pringsheim observed the formation, after some time, of peculiar 

 brown crystalloid, sometimes even crystallised, bodies, attached to, 

 and proceeding from, the chlorophyll corpuscles of the cells, and 

 which he supposed to pre-exist in the latter, the acid merely serving 

 to eliminate them. They constitute his hypochlorin. I have re- 

 peated Pringsheim's experiments with the leaves of various plants, 

 and found the phenomena under the microscope exactly such as he 

 describes. On examining the properties of the hypochlorin obtained, 

 more especially the absorption spectrum of its solution, I arrived at 

 the conclusion that they do not differ from those of phylloxanthin, 

 and that the two substances are, in fact, identical. 



Action of Alkalis on Chlorophyll. 



The action of alkalis on chlorophyll has been less frequently arid 

 less minutely studied than that of acids. This may be easily ac- 

 counted for, seeing that, by the prolonged action of alkalis on solutions 

 of chlorophyll, no marked changes as regards colour or other outward 

 properties take place in the latter, some authors going so far as to 

 say that no change whatever is effected by the action, the chlorophyll 

 merely combining with the alkali to form a saline compound. That 

 alkalis do not effect so profound an alteration in chlorophyll as acids 

 do is true ; still, there can be no doubt that the former do lead to 

 the formation of a substance having quite distinct properties, as I 

 think I shall succeed in showing. 



Chautard,* who was, I believe, the first to study the action of 

 alkalis on chlorophyll, states that when caustic potash is added to an 

 alcoholic solution of chlorophyll, which is then heated, a change takes 

 place in the spectrum, which consists in the splitting into two of the 

 band in the red, called by him " bande specifique," the addition of an 

 excess of acid causing it to appear single again, the doubling re- 

 appearing with alkalis, and so on. The fainter bands of the chloro- 

 phyll spectrum disappeared almost entirely in Chautard's experiment. 



On adding potash or soda to a chlorophyll solution Russell and 

 Lapraikf observed a change in the spectrum, which consisted in the 

 fading out of all except the least refrangible or dominant band, the 

 latter at the same time spreading towards the blue. With a con- 

 siderable excess of alkali the dominant band divided into two distinct 

 bands, in accordance with the observation of Chautard. 



TschirchJ devotes a whole chapter of his " Investigations " to an 



* ' Comptes Kendus,' vol. 76, pp. 570, 1273. 



f 'Journal of the Chemical Society,' vol. 41, p. 334. 



J ' Untersuehungen iib. das Chlorophyll,' Berlin, 1884. 



