OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 105 
thousand specimens of lichens from every part of the known world, and in a large 
proportion of cases, with negative or unsatisfactory results. I have frequently 
examined most anxiously several hundred specimens of a particular genus or 
species,—for instance, Peltigera and Siphula,—without once having the good 
fortune to meet with its spermogones or pycnides. But, on the other hand, in 
the midst of disappointments of this nature, | have been rewarded occasionally 
by the discovery of spermogones or pycnides hitherto unobserved and undescribed. 
It were desirable, further, that the observer should possess an almost unlimited 
leisure. The time consumed in manipulations so delicate,—researches so intricate, 
—is incredibly great. Korrper candidly speaks of leaving such investigations to 
those “die bei grosserer Musse solche subtile Studien verfolgen konnen.”* It 
frequently happens that even a small portion of tree-bark or rock contains several 
lichens belonging to the families of the Graphidec, Verrucarie, and Lecidec. 
Intermixed with the apothecia of these lichens, and with each other, may be a 
variety of spermogones and pycnides. The spermogones and pycnides may 
closely resemble each other in external character, or they may differ consider- 
ably. In either case it is often most difficult, if not impossible, at the present 
stage of our knowledge on the subject, to determine to what species of lichen 
each kind of spermogone or pycnide is to be referred. This is more especially 
the case when the organs in question are very minute, black, and cone-like, as in 
the old genus, erroneously so constituted,—Pyrenothea, which is now found to 
consist almost entirely of the spermogones of other lichens. Such spermogones 
and pycnides are frequently indistinguishable from certain Verrucarie, parasitic 
fungi, and even parasitic lichens; and the only means of deciding as to their real 
nature is by microscopical examination. Again, the spermogones of some lichens, 
as Ricasolia herbacea and R. glomulifera, and the pycnides of others, as Peltigera, 
so closely resemble in external appearance the nascent apothecia of the same 
species as to be indistinguishable therefrom without the aid of the microscope. 
Asa general rule, the parasitic Spheric, with which the spermogones and pycnides 
of lichens are apt to be confounded, are very superficial, removable by the least 
touch from the surface on which they grow—have a black colour, possess an 
envelope or capsule formed of hexagonal or roundish cells in a state of close agere- 
gation, and of a dark brown colour, and contain minute, abundant, brownish, 
simple or 1-septate spores. Sometimes spermogones and pycnides occur alone, 
unassociated with the apothecia of any species; and it is in such a case, unless 
in rare instances, equally impossible to say to what lichens they are referable or 
belong. It is therefore possible, nay perhaps probable, that some of the sper- 
mogones and pycnides which I have referred to particular lichens, may be hereafter 
found, when my researches have been repeated and extended, really to belong not 
to these, but to other species. And it may also be discovered to what lichens 
* Systema Lichenum Germaniz, von Dr G. W. Kozrzer. Breslau, 1855, p. 152. 
VOL. XXII. PART I. 25 
