34 CETRAKIA. 



wider lobes, the margins of which are flecked with white soredia 

 in the manner of some Ramalince, has occurred in the alpine re- 

 gion of the White Mountains, and in Mt. Desert, Me. ; and a nar- 

 rower, but similarly sorediate, sterile plant, near Brattleborough, 

 Vt., J. L. Eussell & C. (7. Frost; and even at the Delaware 

 Water Gap, N. J., Austin. Imperfect spermogones in these 

 sterile plants relate them to the present species ; but I have 

 found no spermatia. The species is in some respects not ill- 

 comparable with narrow-lobed forms of the next. G. com- 



mixta (Nyl.) Th. Fr., especially differing in its oblong-ellipsoid 

 spermatia, is unknown as North American. 



15. C.cillaris (Ach.); thallus cartilagineous-membrauaceous, 

 foliaceous, sinuate-laciniate ; greenish-glaucous becoming brown- 

 ish; beneath brownish and more or less fibrillose; lobes crowded, 

 ascendant, often narrowed and many-cleft, lacunose-uneven, the 

 crenate margins fringed here and there with fibrils ; apothecia 

 marginal, middling-sized to ample; disk dark-chestnut; margin 

 crenulate. Spores sub-spherical, 4i-7 mic. in diam. Spermatia 



oblong, thicker at the ends. Ach. L. U. p. 508. Tuckerm. 



Syn. N. Eng.p. 16; Exs. n. 5. Platysma, Nyl. Syn. 1, p. 308. 



Old rails, very common ; and also on trees ; throughout the 

 Northern, Middle, and Southern States, Mulilenberg in Ach.-L. U. 

 1810, Ravenel, etc. Newfoundland (a blackened state, referred 

 to C. scepincola by Delise), Despreaux. Arctic America (a dwarf 

 form growing on twigs, also referred to C. scepincola in), Herb. 

 Hook. California,, Menzies. 



I5(a). C. platyphylla ; thallus cartilagiueous, rigid, foliaceous, 

 sub-monophyllous ; olivaceous-brown ; paler beneath, the fibrils 

 obsolete; lobes rounded, strongly reticulate-lacunose, and rugged, 

 tuberculate ; apothecia middling-sized, marginal ; disk dark- 

 chestnut, shining; margin tuberculate. Spores sub-spherical, 

 4-7 mic. in diam. 



Trees, British Columbia, Macoun. Yosemite Valley, Califor- 

 nia, Bolander. Thallus pale sulphur-coloured within, but per- 

 haps not always. The lichen has something of the habit of 

 Sticta fuliginosa, but is near to Cetraria ciliaris, from which it 



does not at all differ in the spores. C. ciliaris of the Pacific 



coast, if perhaps smaller, differs in no respect from the originally 

 described plant of the Eastern States; in which last the fibrils 

 are not always present, as they are not always absent in the 



