HABITATS. 243 
as well as some species of Stigmatea and Dothidea. Of the 
genus Spheria, a considerable number are found on dung, now 
included by some authors under Sordaria and Sporormia, genera 
founded, as we think, on insufficient characters. 
‘A limited number of species are parasitic on 
lichens, and one species only is known to be 
aquatic. 
We have thus rapidly, briefly, and casually 
indicated the habitats to which the majority 
of the larger groups of fungi are attached, 
regarding them from a systematic point of 
view. There is, however, another aspect from 
which we might approach the subject, taking 
the host or matrix, or in fact the habitat, as 
the basis, and endeavouring to ascertain what 
species of fungi are to be found in such posi- ey! 
tions. This has partly been done by M. West- ee 
endorp;* but every year adds considerably to ee ere 
the number of species, and what might have ™° 
been moderately accurate twelve years since can scarcely be so 
now. To carry this out fully a special work would be neces- 
sary, so that we shall be content to indicate or suggest, by means 
of a few illustrations, the forms of fungi, cften widely distinct 
in structure and character, to be found in the same locality. 
The stems of herbaceous plants are favourite habitats for 
minute fungi. The old stems of the common nettle, for ex- 
ample, perform the office of host to about thirty species. Of 
these about nine are Pezize, and there are as many spheriaceous 
fungi, whilst three species of Dendryphium, besides other moulds, 
select this plant. Some of these have not hitherto been detected 
growing on any other stems, such as Spheria urtice and Lophios- 
toma sex-nucleatum, to which we might add Peziza fusarioides and 
Dendryphium griseum. These do not, however, include the whole 
of the fungi found on the nettle, since others are parasitic upon 
® Westendorp, ‘‘ Les Cryptogams aprés leurs stations naturelles.’ 
+ Cooke, ‘(On Nettle Stems and their Micro-Fungi,” in ‘‘ Journ. Quekett 
Micro. Club,” iii. p. 69. 
