DIRINA. | LECANO-LECIDEEI, 491 
red with iodine. Spermogones tuberculoso-immersed, with simple 
sterigmata and acicular, arcuate spermatia. 
A small genus closely allied to Leca- 
E NY 
nora, from which it differs chiefly in the 
character of the hypothecium. In this b (| 
respect, as also in their form, the apo- 
thea resemble those of Roccella. 
1. D. repanda Nyl. Mém. Soc. Ly 
Cherb. v. (1857) p. 116.—Thallus LO 
determinate, thick, tartareo-farinose, . 
tuberculoso-unequal, subeffigurate at ‘) 
the circumference, white (Kf-+ yellow, 
CaCl + red); hypothallus white. e 
Apothecia elevated, plano-depressed, 
at first closed, then expanded and di- 
lated, black, cxsio- or white-pruinose ; 
the thalline margin thick, obtuse, 
more or less inflexed; spores often 
slightly curved, 0,027-30 mm. long, 
about 0,004 mm. thick. — Cromb. : 
Journ. Bot. 1871,p.178; Leight. Lich. Fig. 69. 
Fl. p. 235, ed. 3, p. 226.—Parmelia Dirina repanda Nyl.—a. A theca 
repanda Fr, Lich. Eur. (1831) and paraphysis, x 350. 4. 
177 Three spores, X 500. ¢. Ste- 
P : rigmata and spermatia, x 500. 
A plant chiefly of S. Europe and N. Africa which finds its way to a 
few localities in our Islands. The peculiar apothecia are numerous, at 
times crowded and difform with the thalline margin then flexuose. In 
sterile specimens the spermogones are abundant, with sterigmata0,010 mm. 
long, 0,001 mm. thick. The corticolous form (Lecanora Ceratonie Ach. 
Lich. Univ. p. 361, t. 7. f. 5) does not occur with us. 
Hab. On rocks in maritime districts —Distr. Only sparingly in the 
Channel Islands, 8.W. England, and N. Wales.—B. M.. La Coupe and 
Rozel, Island of Jersey. Portland Island, Dorsetshire; Great Orme’s 
Head, Carnarvonshire. 
Subtribe III. PERTUSARIET Nyl. Lich. Scand. (1861) p. 177. 
Thallus variously crustaceous, continuous; gonidial layer con- 
taining typical eugonidia. Apothecia more or less inclosed in 
thalline verruce, punctiform or with the disc expanded and leca- 
noroid; spores variable in number, simple. Spermogones with 
simple sterigmata. 
Arranged by many authors among the Pyrenocarpe: from the fruit of 
both being frequently subsimilar. As, however, the more developed 
forms of the apothecia in Pertusariei resemble those of many Lecanorei, 
its two genera are more appropriately included in this tribe. 
62. PERTUSARIA DC. Fl. Fr. ii. (1805) p. 139; Nyl. Mém. 
