8 
ON MIMICRY IN FUNGI. 
Scleroderma vulgare , Fr. is very like, at first sight, lumps of 
horse dung. 
Fungoid Odours. Before speaking of the odours of various sub- 
stances that are mimicked by fungi, it is advisable to make a few 
remarks upon the subject generally. In the first place there are 
many persons who are to a greater or lesser degree odour blind. 
Neither is there any means of accurately measuring, either the ex- 
tent or quality of odours. To some persons an odour may be in- 
tensely offensive, while others can hardly appreciate it, or may in- 
deed, question its existence altogether. Again, odours which are 
unpleasant to some persons are to others agreeable. The power of 
smell is possessed, as is well known, much more perfectly by some 
of the lower animals, for by it the Carnivora , track their prey in a 
manner totally beyond the ability to do so possessed by any human 
being. Hence, although we may be unable to detect an odour in 
any particular fungus, it by no means follows that that fungus is 
odourless. In the same way some sounds are inaudible to certain 
ears, for example, some persons cannot hear the cry of the bat 
which is heard readily enough by most persons. Having no stan- 
dard by which fungous odours can be accurately compared, mycolo- 
gists have adopted the following, among many other, arbitrary 
terms for indicating the observable presence or otherwise of odours 
in fungi : odour strong, odour unpleasant, odour offensive, and the 
like. When a number of persons are asked to liken the odour of 
any fungus to some known smell, the most diverse similitudes are 
often given. The majority of persons unaccustomed to smelling 
fungi for diagnostic purposes will say it smells “like a fungus” or 
else “ like a mushroom.” A specimen of Agaricus gliocephalus, Fr. 
was once sent to an eminent British fungologist who compared its 
odour to that 11 of rotting broad beans/ 1 Another Agaricus ameides , 
B, and Br. is said by Messrs. Berkeley and Broome “ to resemble a 
mixture of orange flower water and starch,”* while Mr. Berkeley 
says, Agaricus alcalinus, Fr., has “ a pungent odour like fermented 
or putrid walnuts. ”f From these complex comparisons it is clear 
that the difficulty of correctly and concisely describing the odour 
of many fungi is very great. 
Of the 452 species of Agaricus included in Cooke’s “ Handbook of 
British Fungi,” 83 species or 18 percent, have their odours men- 
tioned for diagnostic reasons, but it does not follow that the re- 
mainder are without smell, for such marked odoriferous species as 
A. campestris , Linn. ; A. meleagiis , Sow ; A. rimosus, Bull., &c., are 
passed over without any allusion being made to this character. In 
the genus Lactarius, the percentage is 12, while in Trametes it 
rises to 75, but this is an exceptional genus. Of the 20 species of 
the Hypogei 40 per cent, are mentioned as odoriferous, while in 
the Tuberacei it rises to 55 per cent. To illustrate the manner in 
* Berkeley and Broome, “ Ann. Nat. His.” 1865, No. 999. 
t “ Berk. English Flora,” vol. v, pt. 2, p. 58. 
