rhizocarpon] leoideack^e 187 



mm. long, 0,008 mm. thick; hymeiiial gelatine deep-blue with 

 iodine. — Lecidea scapanaria Carrington in Trans. Bot. Soc. Edin. 

 vii. pp. 382 & 411, t. 10, fig. 4 (1863); Cromb. Lich. Brit, 

 p. 87 ; Leight. Lich. Fl. p. 358 ; ed. 3, p. 387. L. persimilis 

 Nyl. in Siillsk. Faun. & Fl. Fenn. n. ser. i. p. 237 (1859)? 

 Stirton in Grevillca ii. p. 71 (1873); Leight. Lich. Fl. ed. 3, 

 p. 391? 



A doubtful lichen ; the alteration in form of the hepatic noted b}' 

 Carrington rather indicates a fungoid parasite. Further examination 

 with fresh material is desirable. 



Hah. On hepatics. Kare in S. and AV. Ireland and {Jidc Stirton) 

 in Central and E. Scotland. — B. M. Killarney, Kerry; Doughraugh 

 Mt., Connemara, Galway. 



78. RHIZOCARPON Ramond in DC. Fl. Fr. ii. p. 365 (1805). 

 Diplotomma Flot. in Bot. Zeit. viii, p. 381 (1850) pro parte; 

 Mudd Man. p. 218. (PI. 15.) 



Thallus crustaceous, usually with a distinct, dark-coloured 

 hypothallus, or hypothallus sometimes wanting (Diplotomma). 

 Algal cells Protococcus, Apothecia usually dark-coloured and 

 carbonaceous, immarginate or with a proper margin only ; asci 

 8- or fewer-spored ; spores ellipsoid or oblong, mostly rather 

 large, septate and muriform, colourless or brown, usually with a 

 hyaline, mucilaginous epispore (halonate). 



The genus Diplotomyna, as understood by Mudd, included those 

 species in which the hypothallus was but little developed and the 

 apothecia surrounded by the thallus to form a spurious margin. 



1. Rh. perlutllin A. Zahlbr. in Engl. & Prantl. Pflanzenf. i. 

 1*, p. 138 (1905). — Thallus subdeterminate, thin, co]itinuous, 

 rimose, glaucous-white or glaucous-ochraceous (K — , CaCl — ). 

 Apothecia somewhat large, plane, margined, rusty-red or rusty- 

 brown, within subconcolorous, not carbonaceous, the margin 

 usually paler ; paraphyses slender, coherent ; epithecium and 

 perithecium yellow-reddish in thin section ; hypothecium dark- 

 red in the middle ; spores ellipsoid-oblong, muriform, colourless, 

 0,030-42 mm. long, 0,013-16 mm. thick; hymenial gelatine 

 bluish, the asci tawny-wine-coloured wdth iodine. — Lecidea 

 perluta Nyl. in Flora lix. p. 575 (1876); Cromb. in Grevillea v. 

 p. 106; Leight. Lich. Fl. ed. 3, p. 380. 



Has much the aspect of Bh. ochrotropa, a plant of Finland and 

 Madeira, but the apothecia are more brightly coloured ; they are 

 scattered and occasionally approximate. 



Hab. On moist quartzose rocks in an upland mountainous 

 situation. — B. M. Erriff River, Connemara, Galway. 



2. Rh. (Ederi Koerb. Parerg. Lich. p. 232 (1861).— Thallus 

 effuse, thinnish, minutely granular, areolate, yellowish-ferru- 

 ginous (K — , CaCl ■— , medulla I -f ))luish). Apothecia .small, 



