LECANORA.] 



LECANO-LECIDEEI. 



487 



192. L. Heppii Xyl. Xot. SiiUsk. pro F. et Fl. Fenn. Fiirh. n. s. v. 

 (186G) p. 182. — Tliallus effuse, very thin, continuous, greyish-white 

 or sordid-ochrucoous (K — , CaCl — ). Apotliccia minute, concave, 

 brown, the margin entire, at length indexed ; epithocium gyalectoid- 

 impressed ; paraphyses slender, not discrete; spores oblongo-ellii/soid, 

 0,0040-45 mm. long, 0,0015-20 mm. thick; hymenial gelatine 

 bluish, then wdne- or sordid-wine-red with iodine. — Cromb. Lich. 

 Brit. p. 57. — Lecanora squamulosa forma Heppii Leight. Lich. Fl. 

 ed. 3, p. 170. Aearospora cervina 0. Heppii Mudd, Man. p. 100. 

 Myriospora Hejjjni Naeg. in Hepp, Exs. (1853) n. 37. Lecanora 

 squamuhaa forma privvjna Leight. Lich. Fl. ed. 1, p. 185 pro parte. 

 —Brit. Exs. : Leight. n. 19G. 



A rather inconspicuous plant very apt to be overlooked. It is apparently 

 a distinct species, though its claims to be so have at times been questioned. 

 The thallus is often scarcely visible and, as observed by Th. M. Fries 

 (Lich. Scand. p. 216), is rarely minutely verruculose. The form of the 

 minute, usually numerous apothecia give it much the aspect of some 

 young Gyalecta. 



Hub. On arenaceous and calcareous rocks and flints in maritime and 

 upland situations. — Distr. Only a few localities in England and S. Wales. 

 — B. M. : South Downs, Hastings, and Bexley Hill, Sussex ; Lyndhuvst, 

 New Forest, Hants ; Great Ayton, Cleveland, Yorkshire. Llandriudod, 

 Kadnorshire. 





 ^ 



X-3 50 



^0 "A 

 •«. 



1^. 



Q. Apothecia normally lecideine ; thecfe myriospored ; spores simple, 

 minute, colourless. Spermogones with simple sterigmata, at- 

 tenuate at the apices, and ellipsoid, very minute spermatia, 

 {Sarcojyne llass. Geneac. (1854) p. 10.) 



193. L. pruinosa Xyl. in 

 Cromb. Lich. Brit. (1870) p. 57. 

 — Thallus very thin, leprose, 

 greyish-white (K — , CaCl — ), 

 usually obsolete. Apothecia 

 moderate, appressed, plane, 

 reddish-black when moist, black 

 and more or less ciesio-pruinose 

 when dry, whitish within, the 

 margin thin, entire, sometimes 

 undulate ; hypothecium thin, 

 subin color ous; paraphyses slen- 

 der, not discrete, brown at the 

 apices ; spores oblongo- cylin- 

 drical, 0,005-6 mm. long, 

 scarcely 0,0003 mm. thick ; 

 hymenial gelatine bluish, then 

 wine-red with iodine. — Cromb. 

 Grevillea, xix. p. 58. — Lecanora 

 gJaucocarpa forma pruinosa Leight. Lich. Fl. p. 1S3, ed. 3, p. 168. 

 Lecidea pruinosa Sm. Eng. Fl. v. p. 179 ; Tayl. in Mack. Fl. Hib. 



X-500 



Fig. 68. 



Lecanora pruinosa Nyl. — A. A theca 



with parapbysis (separated by K), 



X350. B. Three spores, X 350. 



C. Sterigmata and spermatia, x 500. 



