498 LICHENACEI. [PERTUSARIA, 
Hab. On trunks and branches of trees in wooded upland tracts.—Distr. 
Very sparingly in S. England, N. Wales, and S. Ireland—B.M.: St. 
Leonard’s Forest, Sussex ; near Rusthall Common, Kent; Quarn Wood, 
Isle of Wight; New Forest, Hants; East Lulworth, Dorsetshire; Ivy 
Bridge, 8. Devon ; Island of Anglesea. Castlemartyr, co. Cork. 
_ Form aspergilla Cromb. Grevillea, xix. (1891) p. 59.—Fertile 
verruce scattered, elevated, scarcely margined, white-pulverulent; 
otherwise as in the type Variolaria aspergilla Turn. & Borr. Lich. 
Br. p. 67; Sm. Eng. Fl. v. p. 170; Eng. Bot. t. 2401; Tayl. in 
Mack, Fl. Hib. ii. p. 112. V. communis var. y. aspergilla Gray, 
Nat. Arr. i. p. 491. Lichen aspergillus Ach. Prodr. (1798) p. 28? 
Differs in the character of the verruce; while in the British specimens 
seen the thallus is also thinner. Our plant, which is that of Turner and 
Borrer pro maxima parte, may be different from that of Acharius and 
other authors, who speak of it as only saxicolous. 
Hab. On trunks of trees and pales in upland situations.— Distr. Only a 
few localities in S. and Central England.—B. M.: Ickworth, Suffolk; 
Sevenoaks, Kent; St. Leonard’s Forest, Sussex ; Shiere, Surrey; New 
Forest, Hants ; Gopsall Park, Leicestershire ; Hay Park, Herefordshire. 
11. P. reducta Stirt. Scottish Naturalist, iv. (1877) p. 28— 
Thallus thin, rimuloso-areolate, greyish or greyish-brown (K +yellow, 
then deep red). Apothecia sessile, lecanorine, inclosed in mono- 
carpous thalline verruce, brown or reddish-brown, cxsio-pruinose ; 
spores 0,09-14 mm. long, 0,03-04 mm. thick.—Leight. Lich. Fl. 
ed. 3, p. 229. 
The author says /.c. that it is “closely allied to P. multipuncta;” but 
from this it is widely separated by the type of the apothecia and the 
thalline reaction. I have seen no specimen. 
Hab. On trees in a mountainous region.—Distr. Local and rare in the 
8.W. Highlands of Scotland (Ben Brecht, Argyleshire). 
12. P. lactea Nyl. Flora, 1881, p. 539.—Thallus determinate, 
smooth, rimoso-areolate, subeffigurate at the circumference, greyish 
or whitish (K—, CaCl+reddish). Apothecia lecanorine, small, 
scattered, white, subleprose above, the thalline margin irregular ; 
spores 0,0180-205 mm. long, 0,063-70 mm. thick.—Cromb. Gre- 
villea, xix. p. 59.—Variolaria lactea Gray, Nat. Arr. i. p. 492; 
Hook. Fl. Scot. ii. p. 46; Turn. & Borr. Lich. Br. p. 62; Sm. Eng. 
Fl.v. p. 170; Tayl. in Mack. Fl. Hib. ii. p. 118. Pertusaria lac- 
tescens (3, lactea Mudd, Man. p. 272. ° Lichen lacteus Linn. Mant. 
(1767) p. 182; Huds. Fl. Angl. ed. 2, p. 526; With. Arr. ed. 3, iv. 
p.5; Eng. Bot. t. 2410. 
A plant whose systematic place was doubtful till the recent discovery 
of the fructification, which renders it a very well-marked species, The 
thallus, though orbicular, usually spreads very extensively over the sub- 
stratum, varying somewhat in thickness, the sterile verrucs being at 
times numerous and subconfluent in the areole, With us it is very 
rarely fertile. 
