“e 
250 DR. LINDSAY ON THE SPERMOGONES AND 
These spermogones are sometimes apt to be confounded with nascent apothecia, which 
pierce the thallus as stellate-fissured black points, girt by a pruinose thalline margin. 
The spermatia are abundant straight rods, varying greatly in size, from 3755 to 5500 long, 
4000 
being, perhaps, in the latter case, segmented into halves. Some of them are occasionally 
slightly eurved or twisted. The sterigmata resemble those of Parmelia saxatilis*, com- 
posed of a few simple cylindrical cells. The basal cellular tissue is brownish. The 
pycnides contain small round, oval, or ellipsoid stylospores, sometimes with two polar 
nuclei or granules in their interior, the basidia being very short, inconspicuous, filiform, 
and simple. Similar pyenides occur in connexion with L. parasema, which accompanies L. 
albo-atra, in some of the Yester-House specimens}. The spermogones above described 
can scarcely be confounded, after microscopical examination, with those of either of the 
lichens with which L. albo-atra is here associated; and there is no proper ground for dis- 
sociating the pycnides from albo-atra, and referring them to some unknown and absent 
lichen or fungus. While in the case of L. parasema above quoted, pycnides take the 
place of spermogones, here they occur in addition thereto. 
Specimen 2. On young ash, Dunscombes Wood, Cork, Mar. 1858: Carroll The 
spermogones are small brown dots, scattered among the apothecia, seated on inequalities 
of the thallus, visible only on the application of moisture. Sometimes they have exter- 
nally the characters of those of Lecanora subfusca, being immersed, flat, with no thalline 
ring. The spermatia are acicular, zogo X 25505, on sterigmata that measure about 155 
long with spermatia attached, and that are either simple or digitately divided below. 
In another specimen, associated with Biatora dolosa, Hepp, and Lecanora cerina, 
Ach., are spermogones externally the same. But their cavity is compound, consisting of 
a series of eonverging sinuses; the spermatia are very abundant, straight, but much 
smaller, almost atomic in size, being 4:555 X 55-600 > the sterigmata simple and very 
short. 
Specimen 3. On trees, Glen Nevis, Aug. 1856: W. L. L. The spermogones have the 
same external characters as in the two preceding; the spermatia are abundant, straight 
rods, about 5555 long, seated on long, ramose arthrosterigmata. 
Specimen 4. On old barks, Montford Bridge, near Shrewsbury: Leight. Exs. No. 64. 
On decaying bark, to the left-hand side in my copy, spermogones occur as minute black 
cones that burst through the smooth, thin, white thallus, as the nascent apothecia do. 
Spermatia occur (abundantly) only in one or two spermogones as subatomic, subellipsoid 
corpuscles. The sterigmata are indistinct. 
Specimen 5. On old palings, Switzerland: Hepp Exs. No. 29, sub var. trabinella. 
Spermogones are small black or brown points, crowning separate warts or scales of the 
white, smoothish thallus. The spermatia are very abundant, straight, thickish rods, 
sometimes slightly curved or irregularly twisted. The sterigmata are indistinet, but 
apparently thickish and articulated. 
Specimen 6. On coarse grit, Pinchingthorpe Wood, Yorkshire: Leight. Exs. No. 241. 
* As figured in my ‘ Monograph of Abrothallus, plate v. f. 4; and first Mem. on Spermog., plate xii. f. 19. 
t Vide L. parasema, No. 12, p. 246. 
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