hi THE COLOURS AND PIGMENTS OF PLANTS 53 
soluble in alcohol but not in water, and is said to be 
not improbably related to the aniline dyes—a state¬ 
ment which has also been made for the blue pigment 
found on decaying meat. The pigment of the peach- 
coloured Bacterium described by Professor Lankester 
was found to be very insoluble, but gave a distinct 
three-banded spectrum. 
The pigments of Bacteria have been chiefly studied 
as a means of identifying the organisms producing 
them, and a further account of them here is un¬ 
necessary. Their main interest lies in their frequent 
brilliancy and variety. Bacteria are remarkable for 
the enormous number of chemical substances which 
are the result of their activity ; it would be strange if 
among these there were not some capable of pro¬ 
ducing colour, but the remarkable brightness of many 
of the tints is of considerable theoretical importance. 
The fact that the production of the pigment is a 
factor both of external conditions and of the con¬ 
stitution of the organism suggests that bacteriologists 
may one day have something to say on the general 
problem of the conditions necessary for pigment 
formation. 
With regard to the higher Fungi, it is a familiar 
fact that they frequently display great brilliancy of 
colour. This is especially true of their fructifications 
which on barren ground are often a not inconsider¬ 
able factor in the production of the bright tints of 
autumn. Although these “ toadstools ” are regarded 
with disfavour by many people on account of their 
uselessness for culinary purposes, their beauty, 
especially when seen in natural conditions among 
yellow bracken and glowing brambles, can hardly be 
