112 Jllliio/s Sfdfc LdJxtrdforij of Natiiriil Uisforij. 



2. P. undata Sulliv. Like No. 1 but more rigid, with 

 simple branches; leaves horizontal, triangular-ovate, obtuse, 

 emarginate, or sparingly dentate at the apex, the dorsal mar- 

 gins reflexed and entire, the ventral repand-undulate; amphi- 

 gastria 2-clef t, the segments dentate. 



Hah. — Shaded banks of rivers and wet rocks, Ga. {Suldvant, Les- 

 quereux). 



Bib. — Syn. Hep. p. 659 ; Amer. Jour. Sci. and Arts, 1846, p. 73. 

 Exsic.—Musc. Alleghan. No. 222 ; Hep. Bor.-Amer. No. 10. 



** Under side of stems tvithoiit crestlike lines, 

 f Amphigastria 2-3-cleft.i fugacious. 



3. P. porelloides Lindenb. Stems divided, the branches 

 ascending; leaves somewhat imbricate, convex-gibbous, obovate- 

 rotund, those near the summit of the stem repand-denticulate, 

 the others entire, the dorsal margin reflexed; inner involucre 

 terminal, oblong-ovate, the mouth compressed, denticulate. 

 (Jungermania viticiilosa Schwein.) A variety is P. nodosa, 

 Tayl. 



Hah. — Among mosses in swamps and rivers ; common. The var. in 

 mountain ravines, Canada, N. Eng , N. J. [Austiii). 

 Bib.— Syn. Hep. p. 48, 645. 

 Exsic. — Muse. Alleghan. No. 220 ; Hep. Bor.-Amer. No. 7, 7b. 



4. P. interrupta Dumort. Stems prostrate, copiously 

 rooting, branched, the branches horizontal; leaves imbricate, 

 oval, horizontal, entire or slightly repand; amphigastria lance- 

 olate, 2-3-cleft; inner involucre terminal, broadly obconic, the 

 mouth compressed, repand-crenulate. (P. macrostoma Sulliv., 

 Jungermania interrupta Nees.) 



Hob. — On moist banks and decayed logs; 0. (Sullivant), N. Eng. 

 (Oate), Greenland (Vahl). (Eu.) 



Bib.— Syn. Hep. p. 48, 659; Hep. Europ. p. 44; Sulliv. Mosses U. S. 

 p. 96 ; Torrey Bull. VI, 85. 



DeHn.— Sulliv. Mosses U. S. t. VIII. 



Exsic— Muse. Alleghan No. 221 ; Hep. Bor.-Amer. No. 6. 



ff Amphigastria vanting. 



I 



