5 4 
no doubt tliat leaves which are naturally more or less red, 
such as those of the copper beech and various species of 
colium, contain a ready formed red colouring matter. 
As to the yellow colouring matter of faded leaves, whether 
it pre-exists in the green leaf or is formed from chlorophyll 
or some other leaf constituent, it is not so easy to pronounce 
a decided opinion. This colouring matter, called by Berzelius 
xccnthophyll , is supposed by some to be identical with 
phylloxanthin, the yellow substance which, according to 
Fremy and others, always accompanies the chlorophyll of 
green leaves. Of its properties little is known, and that 
little I find to be more or less incorrect. It is said to be 
soluble in alcohol and ether, insoluble in water, to turn 
green with acids, and to show a peculiar absorption spectrum 
different to that of chlorophyll. These statements require 
correction. It is, in fact, soluble in water, but insoluble in 
ether; it does not turn green with acids,, and the absorp- 
tion bands which it shows are due to an admixture of chlo- 
rophyll, as a few simple experiments are sufficient to show. 
Having taken some bright yellow elm leaves I extracted 
them with boiling spirits of wine, and obtained a greenish- 
yellow liquid, winch, after filtration, showed only the 
dark absorption band in the red corresponding to band 
I. of the chlorophyll spectrum. I evaporated the extract 
in the water bath, and during evaporation observed a 
deposit form on the sides of the dish consisting of 
green fat-like masses. On adding water to the residue a 
portion dissolved yielding a golden-yellow liquid, while the 
fat-like masses remained undissolved. After pouring off 
the liquid and washing the residue with water, the latter 
was dissolved in hot alcoho], when it gave a yellowish-green 
liquid which showed all the absorbtion bands of chlorophyll 
distinctly. The golden-yellow watery solution on the other 
hand showed no trace of absorbtion bands, merely a general 
darkening of the blue end of the spectrum. Its co]our was 
