
OF FILAMENTOUS, FRUTICULOSE, AND FOLIACEOUS LICHENS. 261 
Species 5, S. gelida, L., 
Which occurs in Europe, America, and New Zealand. In Scotland, it is common in 
Skye, and also along the banks of the Caledonian Canal. 
Specimen 1.—New Zealand, CoLEnso; in Herb. Hooker, Kew; on water-worn 
pebbles, precisely as on the banks of our Caledonian Canal. The spermogones are 
very beautiful and distinct. The convexities of the laciniz, about their centre, are 
elevated into a series of aggregated, pale papillee, each having a broadish base, sur- 
mounted by a second or separate cone, of a brownish-yellow colour, pierced or not 
by avery minute ostiole. The interior of the upper cone is found to consist of a 
large brownish-yellow hygrometric kernel, very like the body of the spermegone 
of Periusaria communis, and becoming similarly gelatinous under moisture. The 
spermatia are so extremely delicate as to be almost invisible; they are among the 
most beautiful I have seen. They are vermiform threads, about ;ath long, and 
moth broad. The sterigmata are linear, simple, branching slightly at the base, 
about zcth to guth long. 
Species 6. S. ambigua, Wulf., 
Which occurs in Europe, Asia, and North America. 
Specimen 1.—Madras ; on the bark of trees ; in Herb. Hooker, Kew. The plant 
seldom or never bears apothecia in this country. In this specimen, both apothecia 
and spermogones occur. The latter are minute, brown, immersed, punctiform 
bodies, resembling in external aspect the spermogones of Parmelia saxatilis. 
Species 7. S.aleurites, Ach., 
Which also grows in North America, as well as in Europe. 
Specimen 1.— Franklin’s First Voyage, in Herb. Hooker, Kew (sub nom. Par- 
melia ambigua). This species closely resembles the preceding, with which it is 
constantly associated, and for which it is constantly mistaken. The spermogones 
are punctiform, minute, brown or black immersed bodies, outwardly resembling 
those of Parmelia saxatilis. 
Specimen 2.—Valley of Guttanen, Switzerland; in Herb. Hooker, Kew. The 
spermogones are numerous and very distinct. The spermatia are rod-shaped and 
straight, about anth long, and 34th broad; apparently seated on the apices and 
sides of short articulated sterigmata, about ;,th long, and which resemble those 
of Parmelia conspersa. 
Specimen 3.—On old fir-trees, at Aviemore, 1807; in Herb. Hooker, Kew. The 
thallus is very like that of Physcia stellaris ; but the spermogones and the spores 
equally distinguish the two plants. 
VOL. XXII. PART I. 3X 
