OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 135 
Species 2, A. lata, Tayl. Nyl. 
Syn. Cornicularia, Tay. 
Specimen 1.—Mexico; in Herb. Hooker, Kew. ‘The plant has the aspect of A. 
ochroleuca. The spermogones are plentiful, and easily seen. They are small, 
brown, flattish tubercles or warts, varying in size, scattered about the edges and 
towards the tips of the delicate, filiform, thalline ramuscles. Their bodies are 
immersed in the thallus, and from the fact of the latter being semi-translucent, 
the depth of their immersion can be readily seen. The spermatia and sterigmata 
are as I have already described, and resemble those of Ramalina. 
Species 3. A. Taylori, Hook. 
Speciinen 1.—Kerguelen’s Land; Antarctic Expedition, 1839-48; Dr Hooker. 
In its spermogones, as in its thallus or general aspect, this plant resembles 
Neuropogon, as already described. The spermatia are delicate needles, about xath 
long, resembling those of Parmelia tiliacea, P. physodes, and other Parmelie. The 
sterigmata also resemble those of P. tiliacea in being composed of a few delicate 
linear cells or articulations; others are, however, simple cells, sub-ramose at base. 
The spermatia and sterigmata are among the most beautiful with which I am 
acquainted. <A parasitic punctiform Lecidea, which is apt to be mistaken for sper- 
mogones, occurs on the smooth and thicker part of the thalline ramules. I am 
not aware that it has hitherto been noticed or described, and I therefore propose 
for it the, at least provisional, name of Lecidea alectorie, in reference to its habitat. 
It occurs also, however, on Nephromium cellulosum, Ach. It consists of minute 
round black points, sparingly scattered, flat or depressed, never papillate; they are 
wholly immersed in the thallus of the A/ectoria, and having no thallus of their 
own, the apothecia may be said to constitute the plant. They resemble, in exter- 
nal aspect, the Lecidea vermicularia, which is parasitic under similar circumstances 
on Thamnolia vermicularis, but from which it differs in the characters of the spore, 
which is three-septate, and oval or ellipsoid. The thecz are like those of L. vermicu- 
laria, being obovate and sac-like, irregularly and suddenly bulging, and not tapering 
gradually into a pedicel below as in the majority of thecee. There are no distinct 
paraphyses. This parasite occurs also on the back or lower surface of the 
apothecia of A. Taylori. The spores of A. Taylori are those of our British Usnea 
barbata, and to the genus Usnea, in which it was formerly placed, I am inclined 
to refer it along with the allied Newropogon melaxanthus. 
GENUS V. Evernta, Ach. Nyl. 
The spermogones of this genus are usually punctiform and immersed, of a 
black or brown colour, scattered about the ends of the laciniz on their flat sur- 
