PYCNIDES OF CRUSTACEOUS LICHENS. 261 
removable, black and punctiform, containing stylospores that are oblong, straight, some- 
times very slightly curved, generally l-septate, sometimes simple, usually colourless, 
sometimes of a light-brown tinge, borne on very short, simple, linear basidia. Their 
envelope is of a deep-brown cellular tissue. 
Specimen 5. On Populus nigra, near Laupersville, Switzerland: Scheer. Exs. No. 212, 
sub L. anomala, var. atro-sanguinea. Here, again, pyenides, instead of spermogones, 
occur, of the characters assigned by the earlier lichenologists to Pyrenothea fuscella. They 
are small, brown, and punctiform, scattered over the pale greenish thallus. The stylo- 
spores are frequently, if not generally, l-septate, mostly oval or ellipsoid, sometimes 
oblong or linear-oblong, occasionally pyriform or otherwise of irregular shape, on very 
short, simple, linear basidia. 
This lichen appears to be referred by Mudd (Brit. Lich. p. 184) to var. atro-sanguinea, 
Sch., of the following; which, however, he describes as possessing spermogones only. 
L. luteola, atro-grisea, and incompta are very closely allied, if they are not mere forms 
of a single protean type. They certainly pass into each other by gradations that set 
defiance to specific demarcation-lines. 
Species 27. L. 1rwcoMPTA, Borr. (= Bacidia, Mudd, Brit. Lich. p. 184; Engl. Bot. 
pl. 2699= 2048). 
Specimen 1. On old bark denuded of its epidermal layer, Kildale, Cleveland : Leight. 
Exs. No. 162. The spermogones are extremely minute, black, and punctiform, scattered 
either on the greyish, granulate thallus, or on the bare bark in its immediate neighbour- 
hood. The spermatia are linear, rod-shaped or slightly curved, on simple sterigmata 
resembling those of Opegrapha vulgata. 
Species 28. L. ROSELLA, Pers. (= Bacidia, Mudd, Br. Lich. p. 182). 
Specimen 1. On trees, Friemsberg, Switzerland: Scher. Exs. No. 217: associated 
with Dichena rugosa. On the same bark, associated with the Lecidea, but perhaps 
belonging to the Dichena, or to neither, are pyenides, as scattered, black, round, irre- 
gular, punctiform bodies, with stylospores closely resembling those typical in L. abietina, 
largish, ellipsoid, sometimes obscurely 1-septate, on short inconspicuous basidia. 
Species 29. L. GRIFFITHIT, Sm. (— Biatorina, Mudd, Brit. Lich. p. 176; Engl. Bot. pl. 
1735 —20225). 
Specimen 1. On old oaks, Castlebernard, near Cork: Carroll "Thallus white, cracked. 
Apothecia are black, frequently cæsio-pruinose, flat, distinctly bordered. Spermogones 
are very abundant as largish, black, flattened, very rugose, and cracked, sublecideoid 
bodies, irregular in outline and surface, resembling those of L. Ehrhartiana. Frequently 
also they are quite like young or abortive apothecia; sometimes they have a white thal- 
line border, like the' young apothecia of Zecanora atra. The spermatia are subellipsoid, 
sdso X 35300 On very short, simple sterigmata not above 3755-5000 long with sper- 
matia attached. The cavity of the spermogone is compound; its walls of deep-brown 
cellular tissue. ` 
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