JUNGERMANNIACE^:. (sCALE-MOSSES.) 705 



Stem, bifid; involucral leaves more or less connate, equally bilobed, the lobes 

 entire, obtuse; perianth small, subobovate-i)yriforni, smooth or 1 - 7-nerved or 

 alate both sides. — White Mts., on stunted spruce and birch trees. 



* * Lower leaf-lobe much smaller than the upper. 



1- Underleaves scarceUj wider than the stem, ovate, hijid, the divisions entire, 



acute ; perianth l-carinate or smooth, except in n. 2 ; stems creeping. 



2. F. Virginica, Lehm. Stems short, irregularly branching; leaves 

 crowded, ovate, entire, somewhat concave, the lower lobes sometimes expanded 

 into a lanceolate lamina; underleaves rouud-ovate, bifid, twice the width of 

 the stem; perianth comprcssed-pyriform, tuberculate, 2 - 4-cariuate dorsally, 

 4-carinate ventrally. — On bark of trees, rarely on rocks ; common. 



3. F. Eboracensis, Lehm. Branches clustered ; leaves loose, imbricate 

 on the branches, round-ovate, entire ; perianth pyriform, slightly compressed 

 and repaud, smooth, obscurely carinate beneath and gibbous toward the apex. 

 (F. saxatilis, Lindenh.) — On trees and rocks; common northward. 



4. F. Pennsylv^nica, Steph. Stems dichotomous; leaves imbricate, 

 flat, ovate, nmcronate or rarely obtuse, entire ; lower lobe marginal, large, 

 round-cucullate ; underleaves broadly ovate, deeply parted, the divisions long- 

 acuminate ; dioecious ; antheridial spikes on short lateral branches, elongated ; 

 lobes of the involucral leaves acuminate, mucli narrowed at base, and the 

 large underleaves carinate<'oncave, deeply parted, their apiculate divisions 

 entire or toothed. — Shaded rocks, Stony Creek, Carbon Co., Penn. (Buu). 

 Known only from the original description. 



5. F. saxicola, Aust. Stems numerous, widely branching; leaves or- 

 bicular, scarcely oblique, flat ; lower lobe near the stem, small, or rarely larger 

 and round-galeate ; underleaves scarcely wider than the stem, subovate, bifid ; 

 perianth broadly oblong, bowl-shaped with very short mouth, papillose, abruptlv 

 broad-carinate beneath, 1 - many-nerved each side of the keel, 2-angled. — 

 Sloping dry trap rocks, Closter, N. J. {Austin). 



■^ ■*- Underleaves 2-3 times wider than the stem, round or suhquadrate, hiJid, 



the divisions blunt or truncate. 



++ Leaves lax, rather distant; lower lobe mostli/ expanded, ovate-lanceolate. 



6. F. seoldtis, Nees. Procumbent, irregularly branched or subpinnate ; 

 leaves semi-vertical, subsquarrose, obliquely cordate, the lower lobe expanded ; 

 underleaves ovate, acutely bifid, the upper margin angular-dentate or entire ; 

 sporogoniura unknown. — On trees and rocks, chiefly in mountain regions. 



++ ++ Leaves close-imbricate ; lower lobe galeate, seldom expanded except on 

 terminal leaves. 



7. F. Squarr6sa, Nees. Decumbent, pinnately branching, the short 

 fertile ])ramli lateral; leaves subvertical, suborbicular, obtuse, entire ; lower 

 lobe obovate-cucullate or galeate, subappressed ; underleaves cordate or rounded, 

 sinuate-subdentate, slightly bifid; perianth oblong, tri]uetrous, convex dor- 

 sally, strongly keeled ventrally. — On rocks and trees, N. Y. to Ohio, and 

 southward ; rather common. 



8. F. pl^na, Sulliv. Procumbent, widely branching or subpinnate; 

 leaves orbicular, subimbricate ; lower lobe very small, as broad as long, close 

 to the stem; underleaves rather large, flat, rounded, slightlv bifid ; monce- 



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