Ill 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 



