ON MIMICRY IN FUNGI. 
5 
seems to be exclusively attached to Corticium quercinum , Fr. This 
gentleman, to whom I am indebted for much valuable information, 
says in a letter to me — “ The Coleoptera and Diptera attached to 
fungi would probably amount to two hundred species of each. Then 
you would find a contingent nearly as large of the ichneumons and 
other parasites on these, and the predaceous beetles (chiefly 
Staplylimes ) that devour them.” 
The hymenium in the Phalloidei is moist and gelatinous, and Mr. 
Berkeley says “ it affords a welcome food to multitudes of flies.” * 
It is difficult to see how the spores of these fungi become dissemi- 
nated of their own accord. The spores of our three principal 
British species measure 5 mikromillimeters in length by about 2 
mk. in width ; they are, in fact, very small spores, smaller than the 
Bacillus anthracis which Koch says “may be as long as 20 mk., 
and as thick as 1 to 1-25 mk.”f Every one who has seen any of 
the Phalloidei g rowing must have noticed the cloud of flies that are 
always attracted to them, and there can be little doubt that the 
flies here act the part — to a great extent, at any rate — of spore 
diffusers. 
Many species of Ustilaginei are confined to the interior of 
the ovary, or to the seeds of plants such as Tilletia caries , Tul.; 
Ustilago receptaculorum , Fr. ; U. utriculosa, Tul. ; U. urceolorum , 
Tul.; U. olivacea, Tub; U. montag nei, Tub ; Soiosporium sapo- 
narice , Reed ; Thecaphora hyalina , Fing., &c. Most of these 
have extremely small spores, which could be carried as easily 
as pollen grains by insects from an infected to a healthy 
plant. Anyone who has watched bees must have observed how 
they visit flower after flower, and that they will light upon flowers 
which appear to us to have passed long since their honey-bearing 
stage. One is almost tempted to ask how else could the anthers 
of Silene and Lychius become affected with Ustilago antherarum , 
Fr., unless the spores be implanted upon them by insects, when 
every other part of the plant appears to be perfectly healthy. 
We have seen, then, that insects visit fungi fa) to deposit their 
eggs, where the young larvae shall find suitable and abundant food ; 
(h) for the purpose of obtaining food themselves. 
Let us now see what attractions fungi offer insects as induce- 
ments to visitation. These appear to be of two kinds — (1), external 
appearances; (2), odours, agreeable and otherwise. The outward 
appearance of the larger fungi is, as we have already seen, usually 
in contrast with their surroundings, as anyone who has gathered 
mushrooms in a meadow will readily admit ; but, more than this, 
there are many instances in which fungi mimic other objects with 
great felicity, especially objects from the animal kingdom, either 
parts of animals or animal excrements. 
* “ Berkeley Introduction to Cryptogamic Botany,” p. 347. 
t “ Koch on Traumatic Infectious Diseases.” Translated by W. Watson 
Cheyne ; New Sydenham Society, 1880, p. 58. 
