ad 
PHYSCIA | PHYSIACE% 245 
Essex; near Cirencester, Gloucestershire; Gamlingay, Cambridge- 
shire; Ayton, Cleveland, Yorkshire; near Kendal, Westmoreland ; 
Killaloe, Clare; near Letterfrack, Connemara, Galway. 
Form sorediata A. L. Sm.—Lacinie broader, dilated at the 
tips, closely appressed, the margins and centre almost entirely 
leprose-sorediate, greyish-glaucous. Apothecia not seen. Ph. 
adglutinata £. sorediata Nyl. ex Leight. Lich. Fl. ed. 3, p. 138 
(1879) ; Cromb. Monogr. i. p. 321. 
Exsicc. Larb. Lich. Hb. n. 127. 
Paler in colour than the species, and more entirely sorediate. 
Hab. On walls and trees in upland districts——-Distr. Rare in 
W. Ireland.—B. M. Letterfrack and Mweelan, Connemara, Galway. 
C. Cortex plectenchymatous on both surfaces. 
14. Ph. erosa Leight. Lich. Fl. p. 152 (1871).—Thallus 
suborbicular, moderate in size, composed of mostly short crowded 
imbricate laciniz, minutely crenate or notched, as if eroded at 
the margins, light-grey, often ascending and powdery-sorediate, 
beneath whitish-yellow, sparingly rhizinose (K + yellow, CaCl + 
yellow). Apothecia rather small, dark-brown, pruinose or 
naked, the margin subentire; spores oblong-ellipsoid, 14-20 yp 
long, 7-10 p» thick.—Cromb. in Journ. Bot. x. p. 358 (1872) ; 
Leight. Lich. Fl. ed. 3, p. 139. Ph. cesia var. albinea Cromb. 
Lich. Brit. p. 39 (1870) (non Ach.). Squamaria erosa Borr. 
Engl. Bot. Suppl. t. 2807 (1807). S. tribacita Hook. in Sm. 
Engl. Fl. v. p. 194 (1833). Borrera cesia var. albinea Mudd 
Man. p. 108, t. 2, fig. 31 (1861) (non Ach.). 
Exsice. Larb. Cesar. n. 24 & Lich. Hb. n. 294; Leight. n. 266. 
Closely allied to Ph. tribacia, but differing in the more delicate 
texture and with fewer rhizine. In both species the cortex of the 
lower surface, like the upper, is of small-celled indistinct plecten- 
chyma. 
Hab. On trees, walls and rocks in maritime and upland districts. 
—Distr. Not general nor common throughout the British Islands.— 
B. M. St. Mary’s, Scilly; Rozel, St. Ouen’s and La Moye, Jersey ; 
Jerbourg and Moulin Huet, Guernsey; Penzance and Withiel, 
Cornwall; Plymouth and Wembury, Devon; Porchester, Hants ; 
Bexhill and Washington, Sussex; near Swindon, Wilts; Kingston, 
Somerset; Malvern, Worcestershire; Nannau, Dolgelly, Barmouth 
and Aberdovey, Merioneth; near Ayton, Cleveland, Yorkshire; near 
Staveley, Westmoreland; New Galloway, Kirkcudbrightshire ; Bar- 
caldine, Argyll ; Invermoriston, Invernessshire. 
15. Ph. tribacia Nyl. in Flora lvii. p. 307 (1874).—Thallus 
moderate in size, irregularly orbicular, the lobes short, partly 
imbricate, crenate at the edges, greyish-white, sprinkled with 
small subglobose concolorous soralia which may coalesce into 
sorediate pustules ; beneath brownish-white, with few concolorous 
rhizine. Apothecia moderate in size, blackish, the thalline 
