A Monograph of the genus Inocybe, Karsten. 
BY 
GEORGE MASSEE, F.L.S., 
Principal Assistant , Herbarium , Royal Botanic Gardens , Kew. 
With Plate XXXII. 
T HE word Inocybe was first used by Fries 1 to designate a section 
of the genus Agaricus , which at the time included the majority of 
gill-bearing Fungi. 
Karsten was the first to use Inocybe in a strictly generic sense 2 ; in 
fact this author raised all the sectional names employed by Fries in dividing 
up his huge genus Agaricus to generic value ; a step which has received 
the assent of most modern mycologists. 
The species of Inocybe are by common consent looked upon as difficult 
to recognize in the field ; in fact all past attempts to do so have resulted in 
failure and almost hopeless confusion, and I think it will be generally 
conceded that the Friesian method of study, depending on naked-eye, or 
at most, pocket-lens characters, is wholly inadequate. One principal reason 
for this state of things is the great variability presented by the pileus of 
the same species under different weather conditions. A species may have 
the surface of the pileus normally smooth and silky ; or in other words, the 
specimen on which a species was originally founded happened to have 
a pileus of this nature ; consequently this feature constitutes one of the 
salient characters in its diagnosis, where macroscopic features alone are 
taken into consideration. Unfortunately all who have had a considerable 
amount of experience in the field, know perfectly well that a Fungus usually 
having a pileus of the nature defined above may, under other conditions 
of growth, have the surface of the pileus broken up into scales. Now this 
change technically removes the Fungus from the section ‘ Velutini,’ and 
places it in the section ‘ Laceri.’ As already stated, an experienced 
1 Syst. Myc. Fung. I, p. 254 (1821). 
2 Rysslands, Finlands, och den Skandinaviska Halfons Hattsvampar ; forming vol. xxxii, Finlands 
Natur och Folk, p. 453 (1879). 
[Annals of Botany, Vol. XVIII. No. LXXI. July, 1904.] 
