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capsule project, convergently into the cavity, a series of filaments, 
closely aggregated, called Sterigmata. These are either simple, 
formed of a single elongated cell,— or compound, made up of a 
series of cells, varying in size and form, superimposed the one upon 
the other. They produce from their apices, when simple, — from 
apices and sides, when compound or articulated, — a succession of 
very minute, solid, homogeneous corpuscles, called Spermatia. Just 
as the importance of the apothecia resides in the spores, so the im- 
portance of the spermogones resides in the spermatia. These cor- 
puscles are destitute of any essentially vital motions, though they 
frequently, from their great tenuity, exhibit Brownian or molecular 
movements. Nor are they provided with any such appendages as 
cilia. 
3. Spermogones usually occur on the same plant or specimen 
which bears apothecia : sometimes, however, only on barren plants 
or specimens. Hence, in regard to apothecia and spermogones, 
lichens have been described by continental authors as monoecious 
and dioecious. Again, spermogones occur in some species which 
never bear apothecia, as in Thamnolia vermicularis. 
4. Spermogoniferous states of many species are what were re- 
garded by the older lichenologists as separate varieties, species, or 
even genera, e. g., vars. encausta and vittata of Parmelia physodes , 
and var. denticulata of Platysma nivalis. The discovery, therefore, 
of spermogones and pycnides simplifies lichenology by abolishing 
certain genera, species, and varieties, and materially reducing the 
number of names, e. g. the old genera Cliostomum, Tlirombium , and 
Pyrenothea , being found to consist wholly of spermogoniferous states 
of more familiar lichens, have been abolished. 
5. To a certain extent, or with trifling exceptions, just as certain 
families or genera of lichens are characterised by apothecia and 
spores of a particular kind, so they are also characterised frequently 
by spermogones, sterigmata, and spermatia of a particular kind. 
Thus Usnea and Ramalina have wart-like spermogones of the same 
colour with the thallus, and inconspicuous in consequence thereof. 
The spermogones of Cladonia are barrel-shaped, deep brown, and 
easily visible. Those of Parmelia are mostly punctiform, im- 
mersed, black or brown, very minute and crowded ; those of Physcia 
are mostly papillseform ; and those of Collcma and Leptogium 
discoid, and of a pale brown or yellow colour. In Sticta, Ricasolia , 
