120 DR LAUDER LINDSAY ON THE SPERMOGONES AND PYCNIDES 
only by microscopical examination. The essential difference lies in the character 
of the contained corpuscles—the stylospores, though the sterigmata also differ 
from those of the spermogones to this extent, that they are almost always simple, 
shortish, and stoutish, generating the stylospores only at their apices. The 
pycnides consist, like the spermogones, of a—1. Capsule; 2. Nucleus, made up of 
sterigmata, with stylospores instead of spermatia however; 3. Cavity; and 4. Osti- 
ole. They resemble outwardly, and are frequently mistaken for—a. Spermogones ; 
b. Minute Verrucarias ; c. Parasitic Fungi; and d. Parasitic Lecidee, such as those 
mentioned under the head of spermogones. From all of these bodies they can 
only be distinguished by careful microscopical examination. 
They resemble the organs known as Phoma, Septoria, Diplodia, &c., which, 
according to TuLASNE, belong, as secondary reproductive organs, to various theca- 
sporous fungi. Their occurrence, alike in fungi and lichens, is a strong link binding 
together in close alliance these two great cryptogamic families. They are more 
plentiful in the lower than in the higher,—in crustaceous than foliaceous, lichens,— 
or, in other words, in those species most nearly approaching, in other particulars 
of their organization, the fungi. In crustaceous species they usually occur as 
very minute black perithecia, resembling the apothecia of Verrucaria. But in the 
higher lichens, they are frequently much larger, more closely resemble the sper- 
mogones, and are variously coloured, as in Peltigera and Alectoria. In the first- 
named genus they are marginal, like the apothecia; in the other, they are seated 
sometimes as warts on the thalline filaments, or in the axils of their ramifica- 
tions. 
Pycnides are sometimes associated both with spermogones and apothecia; 
sometimes with apothecia alone, no spermogones being present. Occasionally, 
pycnides and spermogones occur without apothecia, as in some species of Strigula ; 
and sometimes pycnidiferous states of lichens are found just as spermogoniferous 
states are,—without either of the other forms of reproductive organs. 
The distinction between pycnides and spermogones is, to a certain extent, one 
of convenience,—one depending on the difference in character of the contained 
corpuscles,—not one as yet founded on essential differences in function, inasmuch 
as the function of neither can yet be said to be thoroughly established or under- 
derstood. Hence it may hereafter appear that some organs now denominated 
pycnides should be really regarded as spermogones, as those of Peltigera and 
Alectoria, and perhaps, though less likely, the converse,—that some organs now 
regarded as spermogones should be looked upon as pycnides, as those of Lichina ! 
Stylospores have the following distinctive characters :— 
form is very variable; but they are usually pyriform or oval. Generally 
they resemble spores in appearance. They are hollow bodies, with contents 
which are, at least, partly oily. They are usually found intermixed also with oil 
globules of various sizes. Occasionally they are septate, like many spores. Some- 
