243 
of Chlorophyll. 
seemed to have the properties of an organic base. The ex- 
periments were, however, too few, and the amount of substance 
obtained too small to form a basis for positive conclusions. 
The observation, if correct, would tend to confirm the view 
taken by Hoppe-Seyler, who obtained cholin as a product of 
decomposition of his chlorophyllan, and hence concluded that 
chlorophyll itself might have a constitution similar to that of 
lecithin. 
The statements as regards the action of aniline on chloro- 
phyll, contained in the previous communication on the 
chemistry of chlorophyll 1 , have been found on further investi- 
gation to be partly erroneous. For the true or more probable 
explanation of the phenomena which take place when green 
leaves are exposed to the action of aniline, the reader is 
referred to the paper 2 on ‘ The action of aniline on green 
leaves and other parts of plants.’ I still think that in order 
to explain all the phenomena observed, it is necessary to 
suppose that chlorophyll itself undergoes some change when 
brought into contact with aniline while still within the vege- 
table cell. It is possible that the aniline acts in this case as 
a base, producing to some extent the same effect as an alkali 
would. 
It remains to say a few words as to the new facts discovered 
of late with reference to the yellow colouring-matter accom- 
panying chlorophyll in green leaves. These facts are but few. 
Hansen arrived at the conclusion that this colouring-matter is 
identical with that of etiolated plants, with that of faded 
leaves, and with that of yellow flowers : that xanthophyll, 
chrysophyll, erythrophyll, and carotin are different names for 
the same substance, that this substance may be obtained in 
regular rhombic crystals, and that its solutions are non- 
fluorescent and show two bands at the blue end, but none at 
the red end of the spectrum. Professor Hartley, on the other 
hand, states that his yellow chlorophyll gives brownish, 
fluorescent solutions, which show a weak absorption-band at 
the red end, as well as strong bands at the blue end ; from 
1 Annals, iii. 1889. 2 Annals, vi. 1892, p. 167. 
