OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 137 
Species 2. EH. prunastri, Ach., 
Which is less widely distributed than 4. furfuracea; but which, nevertheless, 
occurs in Europe, Africa, and America. 
Specimen 1.—On North Berwick Law, near Edinburgh, August 1855; W. L. L. 
Its spermogones precisely resemble those of the preceding species, being black 
or brown points, abundantly scattered over the lacinize towards their tips. Their 
bodies are wholly immersed, with a simple cavity. Here the spermogones are 
apparently old, as they contain no free spermatia. KorBer describes a minute 
parasitic Spheria as occasionally occurring on the thallus, and which is apt to 
be confounded with or mistaken for the spermogones. 
Sprcies 3. E. Richardsoni, Hook. 
(Sub Cetraria.) 
Specimen 1.—Polar Seas; Drasr and Simpson, Fort Enterprise; in Herb. Hooker, 
Kew. Spermogones abound along the margins of the laciniz as minute brown 
tubercles, giving them a denticulate or nigro-ciliate character, as in Platysma 
nivale. When seated on small tubercles, spines, or cilia, which project from the 
margins of the laciniz, as is sometimes the case, they closely resemble the sper- 
mogones of Cetraria islandica. They are very variable as to size. No free sper- 
matia are found in any of them; they are apparently either old or degenerate. 
The character of the spermogones is, { think, at least one strong reason for asso- 
ciating this plant with Cetraria rather than LHvernia; and I therefore am of 
opinion that NYLANDER has erred in altering Hookrr’s arrangement. 
Species 4. H. Ashneh (t). 
(Syn. Borrera.) 
Specimen 1.—Saharunpore, 1850; Dr Jameson, in Herb. Royal Botanic Garden, 
Edinburgh. The name and place in classification of this plant do not appear to 
have been yet determined. From its general aspect,—its apothecia and its sper- 
mogones,—I am inclined to place it under this genus, beside Z. prunastri and E. 
JSurfuracea. The apothecia resemble those of £. prunastri, and arescattered about 
the ends and over the surface of the laciniz. Its spermogones are punctiform, 
immersed, deep brown, scattered especially about the tips of the lacinie. 
FAMILY [il. Roccrentez. 
GENUS I. Roccsrtua, Bauh. 
The spermogones are generally in the form of minute black points, scattered 
more or less abundantly over the flattened or round segments of the thallus. The 
black points in question are the ostioles, the bodies of the organs being wholly 
VOL. XXII. PART I. 2N 
