A Monograph of the British Gastromycetes. 
BY 
GEORGE MASSEE. 
With Plates, I, II, III, IV. 
Morphology. 
HE group of fungi known as the Basidiomycetes, charac- 
-I- terised by the spores being borne on terminal clavate 
cells or basidia, arranged side by side and forming a con- 
tinuous spore-bearing surface or hymenium, is divided into 
two sub-groups, the Hymenomycetes and the Gastromycetes, 
the former distinguished by having the hymenium exposed 
before its complete differentiation, whereas in the latter the 
hymenium is concealed until the spores are mature and ready 
for dispersion. 
The above expresses the salient features of the divisions from 
the systematises point of view, whose diagnoses almost in- 
variably convey the erroneous impression that the various 
groups under consideration, although related to each other, 
are respectively defined by the characters given, whereas in 
nature, as apart from books, such morphologically isolated 
groups are rare ; the most general experience being that the 
diagnosis only includes in reality the so-called typical repre- 
sentatives of the group, and as we depart from the central 
nucleus of typical species, the characteristic features become 
less and less pronounced and mixed with other characters 
foreign to the typical forms, which by degrees predominate, 
[Annals of Botany, Vol. IV. No. XIII, November 1889.] 
B 
