2 
ON MIMICRY IN FUNGI. 
the remarks of these writers bear chiefly upon the mimicry of one 
species of fungus by an other (interfungal mimicry). This only 
touches the fringe of the subject, and rather trenches upon the 
question of what is entitled to rank as a species, and what as a 
variety. Now this is a highly important question, especially to 
the fungologist, for he labours amongst a group of organisms so 
extensive that no one man can ever hope to master them as 
individuals. They are forms of organic life to which the most 
rabid opponents of evolution have never yet suggested the possi- 
bility of applying the test of hybridization for the differentiation of 
species. Perhaps there is no group of organisms more calculated 
to shake one’s belief in the permanency of species than the one 
under consideration. But to return to the subject of mimicry. 
In the whole range of species included in the Agaricini , in only 
a few instances do we find species protecting themselves by 
mimicking the plants and objects upon or amongst which they 
grow. Of the hundreds of agarics which grow amongst grass, 
in pastures, on lawns, or by road sides, two and two only have 
a green colour, viz., Agaricus ceruginosus. Curt., and Agaricus 
odorus , Bull. ; and it is noteworthy that these are almost the only 
two bright green agarics known, the total number of agarics, with 
any shade of green about them at all, being very small. Now in 
the first named species (A. ceruginosus ) the green colour is not 
permanent, for it disappears pari passu with the maturation of the 
plant. Young specimens have a vivid enough colour, it is true, but 
then it is relieved by dead white floccose scales, which are, how- 
ever, evanescent, and have all disappeared by the time the fungus 
has assumed its whitish yellow hue of maturity. One can hardly 
say, then, that this species has been very succe:-sful in mimicking 
its grassy surroundings, if even it would by so doing gain any 
advantage in the struggle for existence. With the other agaric 
(A. odorus ) it is quite different, for it more closely simulates its 
surroundings. Its colour is not aerunginous, but a much quieter 
shade of green, and it has the odour of “new mown hay,” i.e., of 
Athoxanthum odoratum. It is worth noting that of these two green 
agarics, one is edible and the other poisonous. The other 
instances of agarics, simulating their surroundings, are found 
principally amongst the Derminii , especially amongst the Hebelomce, 
where the humbler shades, brown, grey, or black, are common. 
The great majority of agarics, however, on the contrary, contrast 
strikingly with their surroundings, white, red, yellow, pink, violet, 
orange, and indeed almost every imaginable hue, excepting green. - 
One cannot but be struck with this fact, and conclude that the 
fungi must derive an advantage from it in some way analogous to 
flowering plants. Unfortunately this is only a surmise, as we 
know almost nothing of the physiology of the reproduction of the 
Hymenomycetes ; and hitherto attempts made by experimentalists 
at growing these fungi from their spores have been failures. Mr. 
W. G. Smith, however, has pointed out the strong probability, to 
