140 DR LAUDER LINDSAY ON THE SPERMOGONES AND PYCNIDES 
trast with the white-pruinose disk of the apothecia. These spermogones have the 
usual characters of such as ordinarily occur on the thallus. The spermatia are 
small and curved, about th long, generated on the apex of simple or sub- 
simple short sterigmata. Hence it would appear, that in different specimens of 
the same species, apparently from the same locality or habitat, the spermatia 
and sterigmata differ considerably in character. This, however, is a phenomenon 
we constantly meet with in lichens. On some of the twigs on which the Roccella 
grows, I also find associated with the degenerate lirellee of a Graphis, resembling 
Graphis scripta, a number of small, round, black spermogones, apparently be- 
longing thereto. The spermatia are curved, like those of the Roccella, about 7,th 
long, and borne on the apex of short, linear, simple sterigmata. 
SpPecIES 3. LR. Montagnei, Bel. 
Occurs in equinoctial Africa, India, and Java. This and the following species 
are intermediate, in regard to the characters of the thallus, between R. tinctoria 
and &. fuciformis. 
The spermogones are quite those of the species just named. Indeed there is 
considerable uniformity in the species of Roccella, in regard, at least, to the ex- 
ternal character of the spermogones. Here they are scattered either on the 
general surface, and especially towards the tips of the lacinize, or on the angles of 
the laciniz, when these exist. 
Specimen 1.—Aden, on twigs and rocks; top of Dhemsen Mountain, 1700 
feet high, 1847; Dr Hooker, in Herb. Hooker, Kew. Some specimens closely 
resemble, in the characters of the thallus, the genus Ramalina, in which it has 
been inadvertently placed in the Hookerian Herbarium. 
Specimen 2.—Madras, plentiful on the trunks of the Mangifera indica; ex. 
Herb. Montagne; in Herb. Hooker, Kew. Old spermogones, with lacerate-fis- 
sured black ostioles, are scattered about the ends of the lacinie. 
Specimen 3.—Java, Lobb; in Herb. Hooker, Kew. The sorediiferous tips of 
the segments of the thallus are dotted over with punctiform spermogones, having 
quite the characters of those of 2. tincioria. 
Specimen 4.—Imported, under the name of “ Angola Orchella weed,” from 
the Portuguese settlements of Angola, on the west coast of Africa, into London 
and Liverpool, for the British Orchill manufacture; sent by Messrs BenyJAmIN 
SmirH and Son, Orchill manufacturers, London. ‘The plant grows on the twigs of 
trees and shrubs about the sea-coast. The lacinie are frequently angulose or 
terete-compressed. I find two forms of spermogones. The one occurs as minute 
dark brown points, dotted over the surface of the laciniz, generally in large 
groups or masses. The other is in the form of large, round, or irregular, promi- 
nent, superficial, black tubercles, sparingly scattered, and resembling young apo- 
thecia. In the former the spermatia are curved, delicate, or of great tenuity, 

