FUNGI OF ICELAND 457 
vegetation which condition the growth of the fungi. As actual 
woods are entirely absent in Iceland, or only present in the shape 
of low birch copses in sheltered valleys and on moist valley slopes, 
it might be expected, from the occurrence and distribution of the 
larger fungi in Central Europe, that but few of these would be 
present in Iceland, and that they would chiefly occur in the 
aforementioned birch copses. This, however, is by no means the 
case. For though the number of known species of the larger fungi 
in Iceland is not very great (about 150), the individual species have a 
wide distribution and are very frequent in some localities, even out- 
side the birch copses. In river plains, on mountain slopes, in out- 
lying pastures and homefields, occur, primarily, the larger fungi also 
to be found outside forests in Central Europe, for instance species 
of the genera Mycena, Tricholoma, Omphalia, Russuliopsis, Hygro- 
phorus, Leptonia, Psalliota, Stropharia, Panaeolus, Galera, Naucoria, 
Inocybe, Lycoperdon, and Bovista. But there also occur species of 
genera that chiefly or exclusively inhabit woods, such as Cortinarius, 
Pholiota and Russula. Of these genera Cortinarius is almost exclu- 
sively an inhabitant of woods in Central Europe; but several species 
of it are very numerously represented in Iceland in river plains, 
fiord valleys, and knolly moorland tracts. It would seem, therefore, 
that these fungi do not prefer our woods on account of their trees 
and bushes, but on account of the special climate prevalent there, 
a climate which may be found in Iceland outside the woods, and 
which is especially characterised by a relatively greater moisture 
of the atmosphere than that usually present outside woods in 
Central Europe. 
The sporophores of certain of these fungi show peculiar adapta- 
tions to the somewhat altered environment. Thus, in river plains and 
knolly outlying pastures, among grasses, sedges and mosses, several 
species of the genera Inocybe and Cortinarius occur in dense clusters. 
They have short stems and small pilei, whereas the same species 
in Central Europe, as forest fungi, form scattered sporophores with 
long stems and larger pilei. The advantage gained in the former 
case is that the sporophores, on account of their shorter stems, 
develop in a stratum of the atmosphere in which they are not 
exposed to desiccation, and the numerous small pilei can develop 
just as many spores as the fewer but larger ones. 
Further, veiled forms occur, with the veil so well developed, 
that until they are closely examined, one is apt to regard them as 
