308 PYKEXOCAKPEI [tHROMBIUM 



(1831). Segestrella thelostoma Leight. Ajigioc. Lich. p. 34, t. 15, 

 f. 2 (1851). Lecanora thelostoma Hook, in Sm. Engl. Fl. v. 

 p. 189 (1833). 



Distinguished by the wide depression round the scarcely \-isible 

 ostiole, hence the resemblance to a, Lecanoriae apothecium, 



Hab. On whinstone rocks. — B. if. Egglestone, Durham. 



109. aONaYLIA Koerb. Svst. Lich. Germ. p. 351 (1855). 

 (PI. 45.) 



Thallus CTUstaceous, not corticated. Algal cells Pleurococcus. 

 Perithecia almost sessile, soft in texture, bright- or dark-coloured 

 with a poriform ostiole ; paraphyses slender, free ; asci 4-8 

 spored ; spores acicular, straight or somewhat bent, colourless, 

 multiseptate. 



A small genus, with representatives in North and Central Europe. 

 The ostiole is verj- distinct, and tends to widen out at maturity, 

 causing the perithecia to become aknost disciform. 



1. 6. viridis A. L. Sm. — Thallus bright-green when £i-esh, 

 thin, spreading. Perithecia numerous, shining-black when moist, 

 globose, slightly immersed at the base, the ostiole very distinct, 

 becoming wider ; perithecial wall soft, black, rather uneven on 

 the exterior, dimidiate, the inner wall dark blue-green ; asci 

 elongate-clavate, bent at the base, about 0,140 mm. long, 

 0,010-12 mm. thick ; paraphyses longer than the asci, numerous, 

 thread-Uke ; spores narrowly fusiform acicular, somewhat abruptly 

 narrower upwards or blunt, gradually tapering towards the base, 

 colourless, multi-guttulate becoming multi-septate, 0,060-65 mm. 

 long, 0,002-3 mm. thick. 



The thallus follows the inequalities of the soil, and thus shows a 

 somewhat granular surface ; it is nearly allied to G. sabuletorum, a 

 species found in Central Europe, but differs in the thallus and the 

 much longer spores. 



Hab. — On sandy soil by the side of a path. — B. M. Near Horsley, 

 Surrey (the only locality). 



110. MICR0GL.S;NA Koerb. Syst. Lich. Germ. p. 388 

 (1855) ; emend. Lonnroth in Flora xli. p. 632 (18-58). Thelenellu 

 'SyL in Maine et Loire Mem. Soc. Acad. iv. p. 62 (1858); 

 see also Part i. p. 15. (PI. 46.) 



ThaUus crustaceous, non-corticated. Algal cells Pleurococcus. 

 Perithecia simple, immersed or almost free, globose or conical : 

 paraphyses persistent, branched; asci 2-8-spored: spores ellipsoid, 

 muriform, colourless or brownish. 



1. M. modesta A. L. Sm. — Thallus whitish, thin, continuous 

 or somewhat cracked and unequal. Perithecia embedded in 

 small protuberances of the thallus, subglobose ; perithecial wall 

 soft and colourless at the base, brownish upwards to dark-brown 



