point, narrowly recurved below middle at one side; alar cells 

 few often large, the others oblong-lanceolate. Capsule subobloug 

 oblique not curved; lid apiculate. Tufts dense glossy green. 

 Branches few short not attenuate. Monoecious. Resembles a 

 small state of P. Boesei. — Amer. r. Can.: Macoun. 

 12.P.atteniiatiraineum Kindb. cat. Canad. m. 



Lower leaves broadly ovate obtuse or obtusate, recurved to 

 above middle at least at one side; lower basal cells dilated 

 nearly uniform, the others oblong lanceolate; costa sometimes 

 simple and reaching to middle. Other leaves gradually smaller 

 upwards, narrower, more acute or acuminate. Branches long- 

 attenuate flagelliform above. Tufts loose faintly shining. Cap- 

 sules unknown. — Rocks r. Amer. Can.: Macoun. 

 III. Isopterygium Mitten. 



A. Leaves distinctly denticulate, not recurved. Capsule 

 annulate. 



a. Leaves denticulate nearly all around; alar cells gen. distinct. 

 Monoecious, us. fruiting. 



IS.P.silesiacum Seliger. — Hypnum Sel.; Plagiothecium Br. eur. 



Lea\es ovate-lanceolate long-cuspidate crowded; cells narrow- 

 linear exc. the alar. Capsule somewhat large subcylindric 

 arcuate not striate; teeth pale; lid obtuse; pedicel long. Tufts 

 green. Branches us. curved deflexed. — On logs in woods, r. 

 on rocks. Eur. not r. Sweden common, Norway, Switzerl.! 

 Amer. r. U. S. near Washington: Roell. 

 14.P.turfaceum Lindberg; SuUiv. icon. m. 



Differs from the last: Leaves smaller shorter and less crow- 

 ded, narrowly ovate-oblong shorter-cuspidate; cells linear-lanceo- 

 late. Capsule smaller, narrowly ovate-oblong, striate when dry; 

 pedicel less long. Tufts bright green. Branches us. not cur- 

 ved. — Turfy soil and rocks. Eur. r. Sweden!; S. 0. Lindberg. 

 Amer. not r. princ. in eastern distr.: Macoun; Moser; Waghorne. 

 * P.pseudo-siiesiacum Schimper. 



♦ Lower leaves oval narrowly acuminate spreading, the upper 

 appressed. — Amer. U. S. r.»: Lesq. et Jam. 



b. Leaves distantly denticulate in upper third; cells linear, 

 alar not distinct. Dioecious very r. fruiting. 

 IS.P.elegans Hooker. — Hypnum Hook.; Plagiothecium Schim- 

 per; Sulliv. icon. muse. 



Leaves ovate-lanceolate short-cuspidate often somewhat large. 

 Capsule small obovate or oblong, not or slightly curved; teeth 

 pale; segments entire; cilia long not appendiculate; lid acute or 



