CETRARIA. 29 



2. C.Californica, Tuckerm. ; thallus tufted, fruticnlose, erect, 

 cartilagineous, sab-fistulous, compressed-terete, at length deeply- 

 and canaliculate-lacunose ; dichotomously much- and spread- 

 branched ; greenish-olivaceous, and fuscescent, dull ; apothecia 

 sub-terminal, middling- sized, appeudiculate, the disk dark- 

 green, becoming convex and black, and excluding the toothed 



margin. Spores ellipsoid, -^-mic. Spermogones immersed- 



papillseforni ; spermatia oblong, thickened at each end, -^ mic. 

 Suppl 2, 1. c. p. 203. 



Trees, coast of California (Menzies), Tuckerman I. c. 1859. 



Fences, Oregon, Hall British Columbia, Macoun. Most 



naturally associable with the genus which shall include C. acule- 

 ata\ but agreeing in the spermogones and their contents with 

 C. tristis. 



3. C. aculeata (Schreb.) Fr. ; thallus densely tufted, fruticu- 

 lose, erect, rigid, sub-fistulous, more or less compressed or angled 

 below but teret/sh above; divaricately much branched and the 

 branches beset more or less with black spinules; dark-chestnut- 

 browu, polisheih apothecia sub-terminal, middling-sized, the 

 disk chestnut, the margin toothed. Spores ellipsoid, -yj- mic. 



Spermogoues in spinules ; spermatia oblong, cylindrical. Fr. 



L. E. p. 35. Schcer. Spicil p. 254. Nyl. Syn. 1, p. 300. 



On the earth, and growing over mosses on rocks, in alpine 

 districts. White Mountains, Tuckerman, Syn. N. E. 1848. 

 Newfoundland, Despreaux. Rocky Mountains, Macoun. British 

 Columbia, Macoun. Arctic America, Herb. Hook. 



4. C. odontella, Ach. ; thallus densely tufted, fruticulose, ex- 

 panded, chestnut -brown; the flat, linear, palmately- divided, 

 spinulose branches emitting here and there fibrils beneath, but 

 more or less ascendant ; " apothecia terminal, flat, the disk 



brown." Syn. p. 230. Fr. L. E. p. 35. Th. Fr. Lich. Scand. 



p. 99. 



Growing over mosses on rocks in Arctic America ? The au- 

 thorities (Syn. Lich. N. Eng. p. 14) are all uncertain. C. nigri- 

 cans, Nyl., especially differing in being still more depressed and 

 expanded, with somewhat channelled lobes, and rather distincter 

 fibrils beneath, but known only in a sterile state ; is, however, a 

 native of Greenland ; Th. Fr. I. c. 



f f Thallus turgid, straw-coloured, or now fuscescent, softish. 



