MR GllEVILLE ON THE 
All the eatable fungi are contained in the genera Tuber^ 
MorcJiella, Helvella, Clavaria, Hydnum^ Cantharellus, 
Boletus, Jgaricus, and Amanita; species of all of which 
we possess in this country. 
As a guide in the selection of unknown fungi, colour is 
probably of considerable importance. " Quamobrem recte 
scribit Avicenna^'^ says Mathiolus, eos nocentiores esse, 
qui nigri vel virides, velin nigro purpurascentes visuntur.'''* 
Peesoon remarks, that a pure yellow or golden colour, 
especially in the lamellse of Agarics, denotes a good quality. 
Many excellent species have a very pale or nearly white 
pileus ; some are browo. A vinous red and violet is said 
to be universally wholesome; but orange-red and rose- 
colour, poisonous. In regard to the Boleti more especially, 
all are edible according to De Candolle, Essai, p. 328, 
except, 1^^, coriaceous and ligneous species; Sc?, those 
whose stem is furnished with a collar or annular veil ; Sd, 
those with an acrid taste ; and, 4ith, those whose flesh turns 
to a blue colour on being cut. Wherever this last character 
is perceived in any plant of the order, it always denotes a 
poisonous property. 
An excellent rule, and perhaps the best, in selecting or 
in making experiments upon unknown mushrooms, is to 
taste them. If they are astringent, styptic, or leave a dis- 
agreeable sensation on the tongue (the arriere-gout of 
Peesoon), reject them. Those also that have a pungent 
or unpleasant smell, should be equally neglected. 
Agarics growing in tufts and clusters from the trunks or 
stumps of trees are almost universally to be avoided. 
Fungi, especially Agarici and Boleti, should be gathered 
for the table before they arrive at their full age, as they 
frequently then become tough and insipid. The hyme- 
nium, or that part containing the fructification, should,, 
when it consists of tubes (as in the Boleti)^ be invariably 
