270 DR LAUDER LINDSAY ON THE SPERMOGONES AND PYCNIDES 
plant appears to include Collema synalissum, Ach. L. U. 640; Synalissa Acharii, 
Trevis, Hepp. exs. 89; Collema stygiwm, var. incisum, Scher. Enum. 260. 
According to NytAnper, this species is dicecious,—the spermogones and apo- 
thecia occurring on separate plants. The spermatia are oblong, or oblong-ellip- 
soid, about sath long, and sa,th broad, given off as terminal cells or articula- 
tions from the tips of very delicate, linear, simple sterigmata, precisely like those 
of Ramalina. 
Specimen 1.—Sand-hills, Dunfanaghy, County Donegal, Ireland ; Prof. Dicktg, 
1858. About the name and nature of this plant, | am extremely diffident and 
doubtful. It occurs in very small patches, and only a few fragments were sent 
to me for examination. The apothecia are endocarpous, and constitute spherical 
bulgings at the ends of the laciniz ; they somewhat resemble those of Lichina 
pygmea. The spores are ellipsoid,—1-3 septate,—normally the latter. The 
spermogones appear also to be terminal, small, spherical bodies,—resembling 
outwardly, except as to size, the apothecia,—round which they are clustered. 
The spermatia are sub-ellipsoid, and very small. The sterigmata are not dis- 
tinctly seen. In S. micrococca, a French species, the spermatia are atomic as to 
size, being about smth long, and a little less in breadth, according to NYLANDER. 
GENUS II. OmpuHauaria, DR. and Mont. 
This genus closely resembles Collema in its thallus and in its spermogones,— 
in the latter, both as regards their site, appearance, and contents. 
Species 1. O. pulvinata, Scher., 
Which appears to include Collema stygium, var. pulvinatum, Scheer. exs. 435. 
Specimen 1.—Associated with Pannaria triptophylla, var. nigra ; on limestone 
rocks about Yeadon, Yorkshire; coll. Dr CaArrineron. Of this plant Iam not 
at all sure. I have examined only a small fragment, and that not bearing apo- 
thecia. The spermogones are abundant on the tops of the turgid warts, which 
form, or occur on, the margins of the lobes. They are pale, brownish-yellow, 
immerseddisks, disti nct when moistened from the contrast of their colour with 
the dark bottle-green of the thallus. The spermatia are rod-shaped and small, 
and the sterigmata articulated, just as in Collema. 
GENUS III. ConuEMa, Ach. 
The spermogones of this genus are always immersed in the tissue of the 
thallus, and more or less inconspicuous, unless the thallus is moistened. In this 
case, they become frequently very distinct, from the contrast of their pale, 
brownish, or brownish-yellow colour, with the dark-green of the thallus. They 
are distinctly circumscribed, round, hard disks, when distributed on the flat 
surface of the thallus; when marginal,—seated on the crisped and sub-erect 

