348 



Mr. E. Schunck. 



Journals (continued) . 



Jornal de Sciencias Mathematicas e Astronomicas. Vol. V. 8vo. 



Coimbra 1884. The University. 



Mittheilungen aus oler Zoologischen Station zu Neapel. Band VI. 



Heft 2. 8vo. Berlin 1885. The Station. 



Ungarische Revue. Hefte 8-10. 8vo. Budapest 1885. 



Hungarian Academy. 



" Contributions to the Chemistry of Chlorophyll." By Edward 

 Schunck, F.R.S. Received April 30, 1885. Read May 7, 

 1885. 



Action of Acids on Chlorophyll. 



Every one who has worked with chlorophyll must he familiar with 

 the peculiar effect produced on the addition of acids to its solutions. 

 If an alcoholic solution be taken, the colour of the solution changes 

 when an acid is added from bright green to yellowish-green, and the 

 spectrum at the same time undergoes alteration. After standing 

 some time the solution gives a dark green deposit, which, after 

 separation from the greenish-yellow liquid, shows when dissolved in 

 "boiling alcohol or ether, the spectrum of so-called " acid chlorophyll." 



This change is attributed by some to a simple modification of the 

 chlorophyll ; others consider it due to the formation of products of 

 decomposition. The latter view is, I have no doubt, the correct one. 



In order to obtain the products due to the action of acids on chloro- 

 phyll, I find it best to use hydrochloric acid. Fresh green leaves of 

 any kind are extracted, without undergoing any preliminary treat- 

 ment, with boiling spirits of wine. The extract, which should be of 

 an intense green, is poured off from the exhausted leaves, and 

 allowed to stand for a day or two. During this time, a light green 

 somewhat slimy deposit is formed, consisting chiefly of wax and 

 fatty matters coloured by chlorophyll. 



On examining this deposit closely, it will almost invariably be 

 found to contain, interspersed in the mass, small, red, glistening 

 crystals. These crystals consist of a body first observed by Hartsen,* 

 and called by him, " chrysophyll" a name which it would be well to 

 retain. f The deposit having been separated by filtration, a current 

 of hydrochloric acid gas is passed into the dark green filtrate. This 

 produces at once a dark green almost black voluminous precipitate, 



* " Neue Untersuchungen uber das Chlorophyll," "Chem. Centralblatt," 1875, 

 S. 613. 



f The erythrophyll of Bougarel and the crystallised xanthophyll of other 

 chemists are doubtless identical with chrysophyll. 



