298 PYRKNOCARPEI [tHELIDIUM 



(excl. syn.) & Licli. Fl. p. 436 ; ed. 3, p. 460. V. Auruntn 

 Massal. Gen. Lich. p. '22 (1854) & Syinm. Lich. p. 77 (1855); 

 Cromb. Lich. Brit. p. 112. 

 Exuicc. Mudd n. 283. 



The spore characters recorded are both smaller and larger than the 

 size given by Leighton ; but the 2-celled spores and the pitted sub- 

 stratum are characteristic of all the forms. 



Hah. On calcareous rocks.— jDis^r. Somewhat rare in upland 

 regions. — B. M. Hailey Wood and Tetbuiy near Cirencester, Gloucester- 

 shire ; Bilsdale, Yorkshire ; Morrone, Braemar, Aberdeenshire ; Dun- 

 kerron, Kerry. 



4. Th. Nylanderi Krempelh. Lich.-Fl. Bay. p. 246 (1861). 

 — Thallus crustaceous, thin, greyish-green, brighter green when 

 moist and somewhat gelatinous, cracked-areolate, effuse, with a 

 whitish hypothallus. Perithecia small, scattered, black, hemi- 

 spherical, prominent, at length depressed, the ostiole poriform ; 

 perithecial wall dimidiate ; paraphyses mucilaginous, disappear- 

 ing ; asci ellipsoid-ovoid, about 0,070 mm. long, 0,025-30 mm. 

 thick ; spores 8 in the ascus, ellipsoid, rather blunt at the ends, 

 with yellowish granular contents, 1-septate, 0,022-30 mm. long, 

 0,009-012 mm. thick. — Sagedia Nylanderi Hepp Flecht. Eur. 

 n. 440 (1853). Verrucaria viridis Deakin in Ann. Mag. Nat. 

 Hist. ser. 2, xiii. p. 36, t. 3, fig. 7 (1854). 



There is oidy one small specimen collected by Deakin, but it 

 agrees in all essential particulars with Hepp's species. 



Hah. On sandstone rocks.^ — B. M. Torquay, Devon. 



Spores S-septate. 



5. Th. cataractarum Mudd Man. p. 294 (1861).— Thallus 

 greyish-green, efiuse, thin, somewhat gelatinous when moist, 

 subleprose when dry, sometimes evanescent. Perithecia small, 

 semi-immersed or nearly sessile, subglobose, soft when moist ; 

 perithecial wall dimidiate, black ; paraphyses disappearing ; 

 spores ellipsoid-oblong, 1-3-septate, colourless or pale-brownish, 

 rather large, 0,021-32 mm. long, 0,010-15 mm. thick. — Cromb. 

 Lich. Brit. p. 112 (excl. syn. V. margacea Leight.) ; Leight. 

 Lich. Fl. p. 429 ; ed. 3, p. 459. Sagedia cataractarum Hepp 

 Flecht. Eur. n. 442 (1857). 



Exsicc. Mudd n. 281 ; Leight. n. 319 (as Verrucaria margacea^ 

 var.). 



Hah. On rocks and stones in streams. — Distr. Rare in N. England 

 and in E., S. and W. Ireland. — B. M. Near Ayton, Cleveland, York- 

 shire ; Rosscarbery, Cork. 



6. Th. papulare Arn. in Flora Ixviii. p. 147 (1885). — Thallus 

 greyish or brownish, crustaceous, rather thick and cracked or 

 thinner, furt'uraceous and almost continuous, sometimes almost 

 obsolete. Perithecia large, black, semi-immersed or superficial, 



