274 PYKENOCABPEI [eNDOCABPOS 



passing into brown fungal hyphse (the hypothallus of the hchen), 

 and from this lower stratum the perithecia are developed ; they are 

 true perithecia when first formed, but tend to widen out or collapse 

 above to an almost lecideine form as described by Schserer. Further 

 investigation and more accurate observations of fresh material are 

 necessary to determine the existence of two plants, and the fui^al or 

 symbiotic character of the peritheciuni. 



Hab. On earth on alpine rocks. — B. M. Plentiful on the summit 

 of Ben Lawers. 



104. ENDOCARPON Hedw. Descr. Adumbr. Muse, frond, 

 ii. p. 56 (1788); emend. Th. Fr. Lieh. Aict. p. 257 (1860); 

 A. Zahlbr. in Engler ct Prantl Pflanzenf. i. 1*, p. 61 (1903). 

 (PI. 40.) 



Thallus squamulose, or almost cnistaceous, corticated on both 

 surfaces or only on the upper surface, sometimes rhizinose 

 beneath. Algal cells Pleuroeoceus. Perithecia simple, immersed 

 in the thallus, globose or ovate, with a more or less prominent 

 ostiole and with hymenial gonidia ; paraphyses mucilaginous, dis- 

 appearing ; asci 1-6-, usually 2-spored ; spores elongate-ellipsoid, 

 muriform, at first colourless becoming dark-brown. 



First published as a genus by Hedwig with E. pusillum as the 

 type ; it was finally emended by A. Zahlbruckner to include only 

 those forms that have a squamulose thallus with hymenial gonidia 

 and muriform spores. 



1. E. pusillum Hedw. 1. c. t. 20a, figs. 1-8.— ThaUus 

 squamulose, greyish- or reddish-brown, the squamnles scattered 

 or crowded, small, closely adnate to the substratum, the margins 

 slightly raised and crenate. Perithecia minute, black, with a 

 prominent black ostiole ; hymenial gonidia small, in lines paraUel 

 with the asci or in masses ; spores 2 in the ascus, oblong, 

 becoming brown, slightly constricted in the middle, muriform, 

 and multi-ceUular, 0,045-65 mm. long, 0,014-19 mm. thick. — 

 Lichen irapeziformis Zoega ex Dicks. PI. Cr\-pt. ii. p. 22 (1790) ? 

 L. endocarpon With. Arr. ed. 3, iv. p. 52 (1796) ? Vernicaria Garo- 

 vaglii Mont, in Ann. Sci. Nat. ser. 3, xi. p. 59 (1849) ; Cromb. 

 Lich. Brit. p. 109 pro parte ; Leight. Lich. M. p. 459 ; ed. 3, 

 p. 491 pro parte. Dermatocarpon Garovaglii Mudd Man. p. 270, 

 t. 5, f. Ill (1861). 



Hab. On earth-covered rocks. — Distr. Bare in S. England. — B. M. 

 Thetford, Devon ; Alum Bay, I. of Wight ; cliffe, Bottingdean, Sussex. 



2. E. sorediatum Hook, in Sm. Engl. Fl. v. p. 158 (1833); 

 A. Zahlbr. in Engler & Prantl Pflanzenf. i. 1* p. 61 (1903).— 

 Thallus squamulose, olive-green, brown when dry, the sqnamules 

 mostly scattered, appressed, irregularly lobed, the margins 

 slightly elevated and crenate, under surface pale-grey. Perithecia 

 minute, black, the ostiole powdery, blackish-grey ; spores as in 



