358 LICHENACEI. [lECAXOKA. 



Structure of the spermogoues. The thallii*, wliicli is of moderate size, is 

 often thinly white-pniiuose, especially towards the centre, but becomes 

 citrine when moistened. The apothecia, which are chiefly cential, are in 

 asre subbiatorine. The spermosrones have the spermatia 0,003 mm. long, 

 0,001 mm. thick. 



Hah. On calcareous soil, shell-sand, and in the crevices of rocks in 

 maritime tracts. — Distr. L(^cal, thongh not uncommon where it occurs in 

 the Channel Islands, S. England, and S. Wales. — V>. M. : Quenvis, 

 Island of Jersey : Island of Guernsey. Freshwater Bay, Isle of Wight ; 

 Newhaven and Rottingdean Cliffs, Sussex : Bray Hill, St. jMinver, 

 Cornwall ; Stackpole Coml and Lydstep, Pembrokeshire. 



10. L. elegans Ach. Lich. Univ. (ISIO) p. 485. — Tliallus orbi- 

 cular, appressed, stellate -radiate, thictish, orange- or tawny-red ; 

 lacinife subdiscrete, multifid, convex, torulose (K-f purplish). Apo- 

 thecia moderate, adnata, somewhat concave or nearly plane, conco- 

 lorous (K-f- purplish), the thalline margin entire ; spores ellipsoid or 

 ovoid, 0,011-16 mm. long, 0,006-9 mm. thick. — Cromb. Grevillea, 

 xviii. p. 44 ; Hook. Fl. Scot. ii. p. 50 pro parte. — Placodium elef/ans 

 Mudd, Man. p. 131, t. ii. f. 41 ; Cromb. Lich. Brit. p. 45 : Leight. 

 Lich. Fl. p. 178, ed. 3, p. 163. Squamaria eler/ans Sm. Eug. Fl. 

 V. p. 195. Liilien ehgans Link, Ann Bot. i. (1794) p. 37. — This 

 is the plant of most British authors only in so far as relates to the 

 diagnosis (evidently borrowed from Acharius) given by them, the 

 localities and habitats cited being chiefly erroneous. 



A beautiful lichen, somewhat resembling rJiyscia parietina var. ectnnea, 

 but is of an Arctic or Alt-alpire type. Fjom tbe other species of the 

 subgenus it is easily recognized by the thallus beinsr distinctly corticate 

 on both sides. Elsewhere in Europe it is rather variable, presenting 

 several well-marktd varieties, of which only one has been met with io 

 this countiy. The few British specimens seen are rarely fertile, the 

 spermogoues also being rare, with spermatia 0,003-4 mm. long, 0,(01 

 mm. thick. 



Hah. On granitic rocks in alpine situations. — Disfr. Only very spar- 

 ingly among the N. Grampians, Scotland. — B. M. : Lochnagar and 

 C.iirngorm, Braemar, Aberdeenshire. 



Var. p. tenuis Ach. Syn. (1S15) p. 1S3.— Thallus small, thin ; 

 laciniae narrow, discrete. Apothecia small. — Cromb. Journ. Bot. 

 1885, p. 195. — Lichen eJeijans ft. Unuis Wahlenb. Fl. Lapp. (I8l2> 

 p. 417. Lecanora eler/ans form minor Cromb. Journ. Linu. Soc. 

 Bot. xvii. p. 571. Plaadium eler/ans p. discreia (Scha^r.), Mudd, 

 Man. p. 131. Lichenoides tcnni^^simuvi, scutellis exiguis miniatis 

 Dill. Muse. 175, t. 24. f. 08. 



Differs in the much suiallei thallus, the narrower subfihform discrete 

 radii, and the smaller apothecia. In mo^t Biitish specimens the thallus is 

 minute, with the ladii somewhat scattered, and very sparingly fertile. 



Hah. On calcareous rocks in subalpine situations. — Di.<tr. ^"erv local 

 and scarce in S. Wales, X. England, and amou'r the X. Giampians, 

 Scotland. — B. M. : AVhimbold Rocks, near New Radnor. Raduor.-liire ; 

 East Allendale; Xorthiimbtrhiiid. Craig Guie, Braeniar, .Vberdeciithive. 



