CRYPTOGAMIA. ALG^ f Lichen. 
7 
Crust rough, stony, varying much in thickness, grey white. Tubercles con¬ 
vex, black, sessile, a little raised at the edge, surrounded by a white 
border, rather raised and scolloped when old. Jacq. Outer border of 
the crust black. Linn.— L . cinereus. Linn. Huds. With. Ed. 2.—Mr. 
Griffith thinks that this, the rupicola, and the compositus, insensibly run 
into each other, forming in reality but one species, which he calls L. 
varians. (And Dr. Smith is of opinion, that this plant is only a variety of 
L. ater: so perplexing are the intricacies of this numerous tribe to the 
most accurate and persevering observers. 
Variable Lichen. E.) Rocks, large stones. P. Jan.—Dec. 
Var. 2. Tubercles larger, more elevated, white within, border grey white, 
scolloped, crust grey white. 
Jacq. Coll. ii. 14. 5. b. 
Specimens from Mr. Griffith, agreeing well with the figure of Jacquin, but 
without the leaf-like appearance represented at the edge of it. On fine 
grained granite. 
L. con'fluens. Tubercles very black, not bordered, distinct when 
young, confluent when old; crust blue grey, pale brown or white. 
Web. 2 — Hojfm. Licit. 19. 1.— {E. Bot. 1964. E.) 
Crust grey, a line or more in thickness, wide spreading, cracked, white 
when broken. Tubercles very black, coalescing, so as often to cover the 
whole of the crust. Hoffm. Tubercles cracked on the surface, sunk in 
the crust; oftener rather hollowed than raised, and then obscurely bor¬ 
dered with a smooth black edge. Crust grey throughout, sometimes 
growing on a thin-spread, black ground. 
(Confluent-shielded Lichen. Lecidea covfluens. Achar. Hook. E.) 
Var. 2. Surface reticulated. 
Mich. 54- ord. 37. 7. 
Rocks, England. Dicks. 9.—Scotland. Dr. J. E. Smith. Garreg-wen, on 
limestone rocks ; not common. Mr. Griffith. 
Var. 3. Tubercles globular; crust grey white. 
L. pilularis . (which see.) 
Var. 4. Crust rough, brown, much cracked: tubercles flat topped. 
On stones upon Bettws mountain, Denbighshire. Mr. Griffith. 
Var. 5. Fructifications saucer-like, changing to large black tubercles; crust 
brown, granulated ; granulations large, resembling tubercles. 
Specimen from Mr. Griffith; growing on Schistus. The crust has a pale 
brown outer coat, which within has a greenish cast, covering a white 
matter which forms the principal substance of the crust. It is granulated 
and cracked on the surface ; the granulations large, somewhat elevated, 
and not unlike tubercles. The fructifications are at first like saucers with 
a brown border; this soon disappears, and they rise up in the form of 
large black nearly globular tubercles. 
This curious specimen seems to show that the Lichens conjluens and pilu¬ 
laris are the same plant under somewhat different circumstances of 
growth. Mr. Griffith also suggests, that our 4th var. may be the L. 
pinnatus of Dickson, which I think probable, and is, as he observes, the 
plant in its oldest and most weather-beaten state. 
Var. 6. Crust brown, changing to black. 
In this instance the black colour of the fructifications seems to extend itself 
over the otherwise brown crust. Tubercles gently convex, border brown 
