CEPIIALOZIA PLENICEPS (AUSt.) Lindb. Medd. Soc. Faun. et Fl.
Fenn. 9: 158. 1883.
Jungcrmannia pleniceps Aust. Proc. Phila. Acad. for 222. 1869.
Cephalosia crassillora Spruce, On Cephalozia, 40. 1882.
Gametophyte a short slender prostrate leafy stem; leaves thick, obliquely orbicular, concave, riot decurrent, cleft one-fourth to one-third their length, with acute or somewhat obtuse sinus and acute lobes; leaf-cells rather large, 36-40 p in diameter : monoicous; perianth terminal on a short branch, 2.6 mm. high, obovate-cylindric, fleshy, three cells thick at base, reduced to two cells above the middle ; involucral leaves in about three ranks, ap pressed, fleshy, composed of two strata of cells near the base ; antheridia in the axils of smaller leaves crowded in spikes. Sporophyte a short-stalked oval capsule, o.8 mm. long, en
veloped until maturity in a thin calyptra ; spores about in diameter.
The type locality of Austin's plant was in the White Mount ains of New Hampshire ; that of Spruce's C crassifiora in the Pyrenees. It occurs on the mountains of New England and in Canada, and according to Pearson extends westward to British Columbia ; also reported from California (Howe). It is likely to be confused with C. media on account of its thick perianth, which in section is found to be made up of three strata of cells at base, and two strata if the section is made higher up ; C media is smaller and dioicous, with strongly decurrent leaves and probably has a much wider range in both latitude and altitude. C. pleniceps is also reported from various parts of Europe.