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 Vadium 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 



