Distribution of Fungi. 279 
moisture of the climate and on the nature of their matrix, the 
two mycological zones already distinguished are divisible into 
several regions according to their greater or less amount of 
humidity, and not according to their latitude or their elevation 
above the sea; for these are circumstances that seem to exercise 
little or no influence upon the Fungi. In this fact we get an ex- 
planation why the fungaceous floras of Southern and of Northern 
jurope respectively differ essentially so little that no distinction 
can be justly instituted between them; indeed, with reference 
to this point, it would perhaps be easier to separate Eastern from 
Western Europe. res 
In any region whatever, it is necessary in the first instance to 
draw a distinction between its open naked plains and its wooded 
tracts. In the level open country there is a more rapid evapo- 
ration of the moisture by the conjoined action of the sun and 
wind ; whence it happens that such a region is more bare of 
Fungi than one that is mountainous or covered by woods. On the 
other hand, plains possess several species peculiar to themselves, 
as, for example, Agaricus (Naucoria) pediades, certain Tricholomata, 
and, above all, the family Coprini, of which they may be regarded 
as the special habitat. The species of this. family augment in 
number, in any given country, in proportion to the extent and 
degree of its cultivation ; for instance, they grow more luxu- 
riantly in the province of Scania, in Sweden—a district further 
distinguished aboye all others by its cultivation and fertility. 
Tn well-wooded countries, moisture is retained a much longer 
time, and, as a result, the production of Fungi is incomparably 
greater: and it is here desirable to make a distinction between 
the Fungi growing in forests of resinous-wooded trees (Coniferz) 
and those which inhabit woods of other trees; for these two de- 
scriptions of forests may be rightly regarded, as to their funga- 
ceous growths, as two different regions. Beneath the shade of 
Conifers, Fungi are earlier in their appearance, so much so that 
it often happens they have attained their complete development 
when their congeners in forests of non-resinous trees have 
scarcely commenced their growth. In woods of the latter sort, 
the fallen leaves, collected in thick layers, act as an obstacle to 
the soaking of moisture into the earth, and thereby retard the 
vegetation of Fungi; on the other hand, such woods retain 
moisture longer. These conditions afford to several large and 
remarkable species the necessary time for development. I will 
cite, for example, Polyporus frondosus, P. umbellatus and P, gi- 
ganteus, Hydnum erinaceus, H. coralloides, H. septentrionale, &c. 
The beech is characteristic of our own region; but further north 
this tree gives place to the birch. Coniferous woods are, moreover, 
divisible into two regions—that of the Pines and that of the Firs, 
20" 
