A conrmon Antarctic American plant, rarer in Tasmania, and replaced in Lord Auckland's group by S. tenerum. Its range is very wide in both hemispheres, from within the Arctic circle of the New and Old Worlds, attaining Walden Island north of Spitzbergeu, within 9° of the North Pole, stretching south, throughout Europe, to the Asturias, Switzerland, and Madeira, and in America to Newfoundland.
2. Sph^rophoron tenerum, Laurer. Fl. Antarct. Pt. 1. p. 195. Mont, in Toy. au Pole Sud, Bot. Crypt, p. 172. (Tab. CXCVII. Fig. I.)
Hab. Hermite Island, Cape Horn; most abundant on the hills. Clionos Archipelago, C. Darwin, Esq.
In the former part of this work we have pointed out the characters which distinguish this species from the S. coralloides. It is much more frequent in Tasmania and New Zealand than in South America, in the latter country having been only found at Cape Horn, Euegia, Chiloe, and the Chonos Archipelago.
I know of no Lichen which exhibits so well the successive development of "laminae proligerae" in the same apothecium. A vertical section of the youngest fruit shows two strata, parallel to, or rather concentric with, one another. Of these, the upper is fully ripe long before the bursting of the apothecium. It consists of innumerable filiform asci, containing from eight to thirty and more sporules. The sporules are vertically arranged and so densely packed that each ascus resembles a moniliform filament : the lower are smaller, the upper gradually larger; none however, attain then full size till after the absorption or disappearance of the walls of the ascus; when they escape as spherical bodies, surrounded by a narrow transparent margin.
The thallus of this genus consists of a firm crustaceous transparent cortex, whose inner edge is sharply defined, enclosing a mass of longitudinally arranged, matted, curved, dry filaments. These filaments are cylindrical, terete, sparingly supplied with very short ramuli, and truncate or obtuse at either extremity : they entirely surround the nucleus of the very immature apothecium.
Plate CXCVII. Fig. I. — 1, fertile, and 2, barren specimens, of the natural size ; 3, young, 4, mature, and 5, aged apothecia ; 6, 7, and 8, vertical sections of 3, 4, and 5, respectively, showing the formation of successive laminae prbligerse; 9, asci and spores ; 10, young (or possibly abortive) asci; 11, mature ascus ; 12, spores; 13, cortical and filamentous substance of thallus ; 14, filaments from the latter : — all highly magnified.
3. Sph^erophoron compression, Ach. Fl. Antarct. Pt. 1. p. 196.
Hab. Hermite Island, Cape Horn, and Falkland Islands; on turfy ground, abundant.
These specimens are identical with the English plant so called. It is also an Auckland Island species, and is found in various countries, both within and without the tropics, as far north as the barren lands bordering the Polar Sea in Arctic America. In Europe, Wahlenberg remarks, that it does not occur in any part of Scandinavia. In the Southern Hemisphere it grows on the South American Andes and in Van Diemen's Land.
4. Sph^erophoron australe, Laurer. Fl. Antarct. Pt. 1. p. 195.
Hab. Strait of Magalhaens ; Port Famine; Gwpt.Kimg.
Manifestly identical with the Tasmanian, New Zealand, and Lord Auckland's group species of this name, but not hitherto found elsewhere in the New World.
5. SpH^ROPHORON/'rayffe, Ach.; Lick. Univ. p. 585. Engl. Bot. t. 2474. Mont, in Toy. au Pole Sud, p. 172.
Hab. Strait of Magalhaens ; U Urville.
A frequent Arctic and North Temperate zone plant, reaching the latitude of Igloolik in the American Polar Sea, and, in Europe, Lapland, Spitzbergeu and even Ross Islet, the most northern known land in the world.
