1885.] 
Flowers and Fruits. 
203 
absorption-band between D and F. The varying intensity 
of the colours of roses, carnations, and peonies depends pro- 
bably on the presence of acids. The scarlets and brick-reds 
ol poppies, scarlet lilies, the berries of the dog-rose, &c., 
are produced by the simultaneous presence of lipochrome. 
^ The blue and violet pigments turn pale also in alcohol. 
The solution is reddened by the addition of an acid, as was 
noticed by Fremy and Marquardt. They assumed therefore 
that the red colours were merely blue pigments modified by 
acids. Hansen, on the other hand, holds that the blue and 
violet colours are derivatives of the red. In favour of this 
view is the faCt that certain blue and violet flowers 
(Boraginese) are at first red. [The flowers of Erica cinerea 
are on opening red, but turn more to a violet on fading. On 
the contrary, the corolla of many fuchsias passes from a 
bluish violet to a red.] Salts of iron turn the red of peony 
flowers to a violet. Perhaps their action is similar during 
the life of the plant. It is well known that gardeners can 
produce blue Hortensias by adding iron to the soil. Peony 
red is turned to a violet by the addition of sodium phosphate, 
and larger quantities of the same reagent render it blue! 
The spectrum of the blue and violet pigments has two 
absorption-bands between D and b. These pigments also 
may be combined with lipochrome yellow, thus producing 
the colour of the berries of Ampelopsis. Hansen does not 
refer to the red, blue, and violet colour granules which occur 
here and there in flowers and fruits. He assumes, there- 
fore, only four fundamental pigments Soluble yellow, 
lipochrome yellow, flower-red, and chlorophyll green. He 
opposes the view that all colours are derived from chloro- 
phyll green, since their speCtra do not agree. The change 
of colours of green fruits and green leaves in autumn he 
accounts for by the destruction of the chlorophyll, and 
either the simultaneous formation of new pigments or the 
unmasking of lipochrome which existed previously, but 
which was concealed by the chlorophyll. Brown decompo- 
sition products cooperate in the production of the autumnal 
colours. 
