278 M.E. P. Fries on the Geographical 
pointed out in the present state of our information respecting 
their fungous inhabitants. However, these statements are not 
to be interpreted to signify the existence of any well-defined 
limits; for either one of the zones described passes insensibly 
into the other in countries intermediate in position, as is espe- 
cially illustrated in North America, where the tropical forms of 
Fungi extend themselves far northward. 
The characteristic differences of the two zones are obscure in 
the case of the lower orders of Fungi, but much more striking 
in the higher forms. They are particularly evident in the Gas- 
teromycetes, several genera of which are the denizens specially of 
tropical lands, and among the Hymenomycetes, which in these 
same regions assume a tough and woody consistence, whereas in 
the cold and temperate zones of the globe they become more 
fleshy, and are decomposable with greater rapidity. It has for 
along time been the belief that the fungaceous vegetation of the 
tropics was poor, because it was imagined that the heat would 
arrest its development ; but more attentive observation proves 
the fallacy of this opinion. It is only in the most arid regions 
of the earth that a distinct fungaceous flora appears to be want- 
ing. In the primitive forests of tropical countries the presence 
of Fungi is not connected, as it is in these temperate regions, 
with a particular season; it is constantly the same throughout 
the year. 
Whilst the species of Fungi in the temperate zone are distri- 
buted in a very uniform manner, they appear to follow, on the 
contrary, in tropical regions, a more special plan of diffusion 
in the several countries. However, there are Fungi that may 
be called cosmopolitan, such as Agaricus (Amanita) muscarius, 
A, (Psalliota) campestris, A. (Naucoria) pediades, Schizophyllum 
commune, Polyporus versicolor and P. igniarius, Lycoperdon gem- 
matum and Lycogala epidendron, &e. 
Great differences have been noticed, in reference to their funga- 
ceous vegetation, between Cuba, Java, and the PhilippineIslands; 
yet in all these countries the preponderance of the Polyport is a 
fundamental or characteristic feature. That the fungaceous floras 
of very distant countries may be very similar is distinctly shown 
in the instance of North America, which possesses the majority 
of European species, besides those others peculiar to itself. The 
island of Juan Fernandez, which has been very carefully explored, 
presents a fungaceous vegetation differing in only one-third of its 
forms from that of Europe. The same holds true, it is asserted, 
with respect to the Fungi of New Zealand and of Australia, 
although these countries do also possess indigenous genera un- 
known in Europe. 
Since the Fungi are less dependent on heat than on the 
