60 
LICHENS. 
completely with those distinctive characters that are unhesitatingly 
employed by all lichenologists. The colour of the apothecia, the 
spores, and the thallus are regarded as furnishing characters of 
great importance, and as these characters are derived from the 
presence or absence of colouring matters, why not arrive at the 
same systematic results from a study of the reactions of these same 
organs. In cases where varieties, species, or groups are dis- 
tinguished by the colour of certain organs it might be attended 
with greater scientific precision by showing to what chemical sub- 
stances these differences are due. 
New or Rare Lichens, by G. Massee. 
Lecanora Pollinii (MassaZ.) .=Blastenia Pollinii, Massal. Syn. 
Lich. Blast., p. 15; Massal. Mon. Lich. Blast., p.\M,fig. 27; 
Lecanora nigricans, Tuck. ( fide Nyl .). Lecidea gibberosa, Pollin 
(non Ach .), Flor. Ver. hi., p. 408. 
1-3 and 5, Lecanora Pollinii ; 4, Lecanora 
ferruginea. 
Thallus thin, white when 
young, then greyish-white, 
glabrous, continuous or indis- 
tinctly cracked into areolae ; 
hypothallus darker; hypothecia 
1-2 m.m. across, scattered or 
crowded, circular or variously 
waved ; at first brick-red with a 
brown tinge, plane, with a dis- 
tinct margin, becoming blackish, 
convex, and immarginate ; hy- 
pothecium dingy ochraceous ; 
asci clavate, 8-spored ; para- 
physes slender, slightly incras- 
sated at the apex, transversely 
septate ; spores elliptical, ends 
rather acute, colourless ; protoplasm occupying a subglobose 
cavity at each end of the spore, and connected by a delicate strand 
through the broad, median septum, 15-16 X 8-9 p; gonidia 
protococcoid, 7-11 p diameter. 
A specimen in the Leighton Herbarium at Kew. Collected in 
Yorkshire. 
Considered by some continental botanists as a variety of Leca- 
nora ferruginea (Huds.), Nyl., but raised to specific rank by 
Massalonga, and distinguished from L. ferruginea by the brownish 
brick-red apothecia becoming very convex, immarginate, and 
blackish with age, the distinct ochraceous hypothallus, and the 
broader and more pointed spores. The hymenium becomes purple 
or crimson with Kho, due to the solubility of the pigment in the 
tips of the paraphyses. The asci become deep blue with I. 
Fig 1, Lecanora Pollinii, ascus with spores, two paraphyses, and 
two free spores, x 400 ; fig. 2, sections through apothecia at 
