
OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 251 
apothecia. The thallus has a grayish or very pale greenish colour, apparently 
_ due to a deficiency of chlorophylle, from growing in damp, dark situations. Hence 
the orange-coloured cone-like spermogones are very apparent; they are also 
very abundant; and not being pierced by distinct ostioles, they cannot be con- 
founded with the nascent apothecia, which, besides their different form (always 
showing the rudimentary disk and exciple), have uniformly a much paler colour. 
The spermogonal envelope is composed of beautiful hexagonal cellular tissue, the 
cells being full of yellow colouring matter ; this tissue is similar to that of the corti- 
callayer of the thallus. The spermatia are sub-ellipsoid, and about ;,nth long; the 
sterigmata are delicate, indistinct, and very closely aggregated into a compact tissue. 
Specimen 2.—On walls, Grange, Edinburgh, 1852, W. L. L. The spermogones 
/ are small, sometimes indistinct, cones or papille, of a deeper orange than the 
thallus, having no perceptible ostioles. They are distinguishable from the young 
apothecia by their rounded apex and their darker colour. 
Specimen 3.—LrE1cHTon exs. 10 (E. B. 194); Berwick, near Shrewsbury, Shrop- 
'shire. The spermatia are innumerable, and indistinct from their minute size. 
Exs. 11, sub. var. sub-stellata, Fr. (E. B., 1794); also from Berwick, near Shrews- 
bury. ‘The thallus bears no apothecia, and only a few spermogones. HEpp. exs. 
54 (sub. var. polycarpa, Sch.) This is a dwarf form, with abundant, crowded 
| apothecia, common on fruit-trees; its spermogones are those of the type. 
Specimen 4.—ScHZRER exs. 380 (sub @. vulgaris); on wood and stones in open 
| places, Switzerland. The spermogones are small, distinct, orange-red papille, 
| without distinct ostioles; the whitish hard kernel, which constitutes the body of 
| the spermogone, can be readily enucleated. The spermatia are sub-ellipsoid, and 
about wonth long; the arthrosterigmata are about zth to jth long. 
Specimen 5.—Var. laciniosa, Sch., a form marked by small lacinize, much dis- 
| sected or subdivided. ScH#RER’s exs. 381 (sub 6. laciniosa, Duf.); on old trees in 
hilly and alpine districts, Switzerland. The spermogones have the usual site; but 
| they are of a very bright red, almost vermilion, colour; they are few, and sparingly 
scattered. Exs. 383 (sub & fulva); on palings, about Samaden. This plant seems 
_referrible to var. /aciniosa. Along with the ordinary spermatia and sterigmata of the 
| type, there occurs in the same specimen, and apparently in the same spermogone, 
occasionally, abundance of curved, linear, or filiform spermatia, about sth long. I 
| have not met with them elsewhere in this species, and am therefore disposed to 
regard them as accidental, and not properly belonging thereto. Exs. 549 (sub. 
var. lychnea, Fr.); on trunks of trees in open places. The spermogones are few, 
| scattered ; the sterigmata are very delicate and indistinct ; the spermatia are about 
month to izooth long, and sath broad—almost atomic in regard to size. 
Species 14. P. candelaria, Ach., 
’ Which occurs in Europe and North America. It closely resembles var. laciniosa of 
| P. parietina, but is distinguished from that species by its thecee having 20 to 30 
