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Umbilicaria , Collema, Leptogium, Thamnolia, Coccocarpia , and 
Placodium, the sterigmata are articulated, consisting of numerous, 
short, broadish, frequently thick- walled, cells. They are also 
articulated or compound, — but the component cellules are few, 
longish, and delicate, — in Usnea , Neuropogon, Parmelia, Evernia, 
and Platysma. They are simple and filiform in Ramalina , Cla- 
donia, Ephebe , and Lichina. The spermatia of Cladonia and Roc- 
cella are curved or sickle-shaped. Those of Squamaria are very 
long, slender, and twisted or curved. Those of Collema, Leptogium , 
and Umbilicaria are short, straight rods ; while those of Ramalina , 
Ephebe , and Lichina , are oblong or oval-oblong. 
6. The spermogones sometimes of themselves yield important 
characters for classification. For instance, the spermogones, sterig- 
mata, and spermatia of Thamnolia vermicularis are sufficient of 
themselves to separate this puzzling lichen from the genus Cladonia , 
in which it has hitherto been almost uniformly placed. 
7. Spermogones frequently outwardly resemble, and are there- 
fore apt to be confounded with — 
a. FTascent apothecia, as in some Ricasolias ; 
b. Pycnides, described below ; 
c. Minute V err ucarias ,< or 
d. Minute parasitic fungi, chiefly of the genus Sphceria. 
For instance, the author frequently receives from correspondents 
as new V err ucarias what prove to be merely spermogoniferous 
states of other lichens. From all the bodies above named, sper- 
mogones may at once be distinguished by microscopic examination, 
and by this alone. 
8. The spermogones of lichens are now generally regarded as 
male organs of reproduction — the spermatia being supposed to be 
analogous in function to the antherozoids or spermatozoids of other 
cryptogams, and to be endowed with a fecundating or fertilizing 
influence on the spores. But it is necessary to state distinctly that 
this is a mere hypothesis, for direct or distinct proof is still wanting. 
The following circumstances, however, give great support to this 
hypothesis, and ought, at all events, to be borne constantly in mind in 
all speculations on the functions of the spermogones and spermatia : — - 
a. Intimate relation between the spermogones and apothecia in 
regard to site — the former being generally seated in close 
proximity to the latter. As illustrations of this intimate 
