274 PYRKNOCAllPKI [eNDOCARI'ON 



passing into brown fungal hyphic (the hypothalluB of the lichen), 

 and from this lower stratmu 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 Schaerer. Further 

 investigation and more accurate observations of fresh material are 

 necessary to determine the existence of two plants, and the fungal or 

 symbiotic character of the perithecium. 



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. Lich. Arct. p. 257 (1860); 

 A. Zahlbr. in Engler & Prantl Plflanzenf. i. 1*, p. 61 (1903). 

 (Pi. 40.) 



Thallus squamulose, or almost crustaceous, corticated on both 

 surfaces or only on the upper surface, sometimes rhizinose 

 beneath. Algal cells Pleurococcus. 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. pusillu7n 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. I. c. t. 20a, figs. 1-8.— Thallus 

 squamulose, greyish- or reddish-brown, the squamules 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 parallel 

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

 becoming brown, slightly constricted in the middle, muriform, 

 and multi-cellular, 0,045-55 mm. long, 0,014-19 mm. thick. — 

 Lichen trapeziformis Zoega ex Dicks. PI. Crypt, ii. p. 22 (1790) ? 

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

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

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

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

 t. 5, f. Ill (1861). 



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

 Thetford, Devon ; Alum Bay, I. of Wight ; cliffs, Kottingdean, 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 squamules 

 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 



