PYCNIDES OF CRUSTACEOUS LICHENS. | 239 
Specimen 6. Var. turgida, Sch. On compact felspar, Craig Rossie, Dunning, Perth- 
shire, April 1858: W. L. L. Some forms have quite the characters of Lecidea ambigua, 
Ach. (Nyl. Prod. p. 133). Spermogones are abundant and distinct, varying greatly in 
their character, partly with age. They are mostly scattered about the boundary of the 
thallus. In the young state they are white, thalline papillæ, which gradually show a 
black ostiole, and have a black interior. "The ostiole enlarges till it acquires the aspect 
of a nascent hymenial disk. It is usually stellate-fissured, subsequently acquiring a 
crenulate margin, and then resembling the apothecia of Lecidea coarctata, Ach., in 
. eertain stages of growth. When old and patent, the spermogones are sometimes as large 
as various Lecanorine apothecia, which they greatly resemble, the border being usually 
thickish, excipular, and very irregular. Thus they have sometimes an urceolate cha- 
racter, like the apothecia of various forms of Lecanora cinerea. In these old states no 
spermatia need be looked for; they are to be found only in the young papillæform sper- 
mogones. The spermatia in question are straight rods, 3555 long, and 554555 broad; 
seated on sterigmata tso long, composed generally of about two delicate, but irregular, 
articulations. 
Another form of spermogone is wholly immersed, occurring on the corners of the 
thalline scales as small, round, pretty regular, flat, black spots, girt by a pale thalline 
ring. The spermatia here also are straight rods 3553 long and 55,55 broad, borne on 
sterigmata about 1757 long, either branching digitately below, or composed of 2 articu- 
lations, as in the preceding forms. These spermogones are to be found in specimens 
having the character of L. ambigua. 
Specimen 7. Var. turgida. On basalt, co. Antrim : Dr. Moore, in herb. Carroll. Ona 
separate portion of the stone there is a tawny, crustaceous, thin, apparently rudimentary, 
thallus, darker in colour than that of the Lecidea, destitute of apothecia, but studded 
over with very abundant spermogones, which constitute an isolated Pyrenothea-like 
group. They are largish, frequently flattened, or subannular; or small subprominent 
papille, closely resembling the perithecia of a Verrucaria (e. g. chlorotica or fusiformis). 
They are sometimes seated on gentle elevations of the thallus. The cellular envelope is 
deep brown, of dense tissue. The spermatia are straight rods, 5555 to 5500 long, and 
zooo broad; on very short, simple, sterigmata, not above 3555 long, with spermatia 
attached. Though associated with, these spermogones may not be really referable to, 
L. contigua or any of its many forms. 
Specimen 8. Var. turgida. On Old Red sandstone ; Kilcully, Cork, March 1858 : Car- 
roll Thallus bluish-grey, smoothish. Spermogones very distinct and abundant, scat- 
tered all over the thallus, but especially about the periphery, as small, black, irregular, 
though generally roundish, spots, with immersed bodies. The spermatia are acicular, 
3000 tO 3000 long, and 45,554 broad, very slender and abundant. The sterigmata re- 
semble those of various Parmelia* (e. g. caperata), about 355 long, and 445,55 broad, 
composed of a few delicate, narrow articulations. 
On a separate, whiter, sterile thallus, belonging, however, to the same Lecidea, occurs 
* As figured in my first Mem. Spermog., plate xi. fig. 14, and elsewhere in same memoir. 
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