PYCNIDES OF CRUSTACEOUS LICHENS. 285 
 lirellzeform, sometimes substellate, character of the latter. Spermatia are rod-shaped, 
3000-9000 long. Sterigmata simple, linear, 43/55 ^ 3055, branching slightly below. 
Species 3. S. Hurcuiwstg, Leight. (Mudd, Br. Lich. p. 243— Platygramma, Leight.). 
Specimen 1. Keswick, Cumberland ; and Newton rocks, Cleveland, Yorkshire : Leight. 
Exs. No. 130. Spermogones are very minute, deep-brown or black, punctiform bodies, 
scattered usually in small groups about the periphery of the greyish or pale brown, thin, 
tartareous thallus, outside the region of the apothecia. Here they occur on a white thallus 
outside the centre patch. Spermatia very minute, rod-shaped, on sublinear sterigmata, 
digitately divided below. 
Genus V. PLATYGRAPHA. 
Species 1. P. PERICLEA, Ach. 
Specimen 1. On bark of firs, Mount Gurnigel, Switzerland: Scheer. Exs. No. 313, sub 
Parmelia exigua, Ach., var. abietina. Spermogones are black and punctiform, scattered 
about the apothecia. Spermatia abundant, linear, thickish, curved, with rounded ends, 
1000X 15000) On short, linear, simple sterigmata. According to Nylander (Prodr. 
p. 162), the spermogones of this species constitute Pyrenothea stictica, Fr. They can 
only, however, do so in part; for we have already seen the said Pyrenothea is also partly 
made up of the spermogones of Arthonia impolita, Opegrapha vulgata, Lecidea abietina, 
L. luteola, and L. dryina. 
Genus VI. MELASPILEA. 
Species 1. M. DEFORMIS, Sch. 
Specimen 1. On walnut, on the Island of St. Petre, Switzerland: Scher. Exs. No. 283, 
sub Opegrapha cymbiformis, var. deformis. The plant is certainly very like Opegrapha 
varia, from which, however, its 1-septate sporidia inter alia separate it. Spermogones 
are abundant as small, black, conoid or punctiform conceptacles, containing acicular 
spermatia, 3060 — 21000 X 25000. On Short, apparently simple, sterigmata. Basal cellular 
tissue deep brown. 
Genus VII. Mycororum. 
Species 1. M. ELABENS, Flot. (Nyl. Prod. p. 171— Zecidea, Schær.). 
Specimen 1. On the bark of old pines, Switzerland: Hepp Exs. No. 230. "Thallus is 
made up of a series of white granulations or tubercles. On these, scattered among the 
apothecia, are seated small, black punctiform spermogones, containing very small, rod- 
shaped spermatia, borne on sterigmata that are not distinetly seen, but some of which 
appear to be simple, while others are articulated. 
Tribe IV. PYRENOCARPEI. 
Genus I. ENDOCARPON. 
Spermogones are frequently more abundant than apothecia. They are also undistin- 
guishable from young apothecia unless by microscopicalexamination. From mature ones 
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