54 
COLOUR IN NATURE 
CHAP. 
denied. It is not, however, the conspicuous forms 
only which are brightly coloured. A species of Peziza 
produces the brilliant green colouring matter which 
so often stains decaying wood, and the yellow spots 
which PEcidium causes on the leaves of the barberry 
are common enough objects in spring. Zopf has 
devoted considerable attention to the pigments of 
Fungi, and has examined many of them. He has 
shown that many Fungi contain one or several 
different lipochromes, and, as has been already 
mentioned, these lipochromes may be taken up un¬ 
altered by parasites. We have also already noticed 
Zopf’s view that the lipochromes function as reserves. 
Besides the lipochromes, a very large number of pig¬ 
ments in Fungi have been described and named. 
The chemical characters of some are known, of others 
unknown, but in few cases, if any, has any definite 
function been assigned to them. Thus we find in 
the Fungi a great number of pigments of very diverse 
colours and chemical composition and of unknown 
function. Notwithstanding this last fact, the colora¬ 
tion exhibits some at least of the characters displayed 
by organisms whose colour is thought to be of supreme 
importance to them. In the large toadstools the 
bright colour is usually confined to the upper and 
conspicuous surface of the pileus , and this surface 
is not infrequently marked or spotted with great 
regularity. These facts are of considerable import¬ 
ance with regard to theories as to the (proximate) 
origin and meaning of colour. They show us that 
not only pigments, but also regularity of coloration 
may occur in organisms in cases where the relations 
to other organisms are too simple for us to suppose 
