DICRANACEAE 2J 



Key to Genera 

 i — Leaves not papillose; capsule inclined and strumose, peristome 



teeth bifid Oncophorns 



Leaves smooth or slightly papillose; capsule erect, teeth not bifid. 



Rhabdoweisia 



Leaves papillose 2 



2 — Capsule erect and symmetric; peristome teeth mostly undivided. 



Oreoweisia 

 Capsule from nearly erect to unsymmetric and nodding, peristome 

 teeth divided about half way Dichodontium 



RHABDOWEISIA B. & S. 



Small mosses growing in dense tufts or cushions, often in 

 damp shaded crevices of rocks and overhanging ledges. Leaves 

 lanceolate to linear, more or less crispate, smooth or mamillose 

 rather than papillose. Capsule erect and symmetric, 8-fur- 

 rowed when dry; peristome teeth narrowly lanceolate, without 

 median line. 



R. denticulata (Brid.) B. & S. "On rocks in ravines, Pas- 

 cack, N. J., and Rockland Co., N. Y.," Muse. App. 72; Red- 

 ding, Ct., Bx! Summer. 



OREOWEISIA De Not. 



Small compactly tufted rock-growing mosses. Leaves ovate- 

 lanceolate to linear-lanceolate, somewhat crisped; lower leaf 

 cells rectangular, smooth; the upper papillose (mamillose) on 

 both sides, square to roundish. Capsule erect, not furrowed; 

 teeth lanceolate, entire or divided. 



O. serrulata (Funck.) DeNot. "On perpendicular face of 

 moist rocks, Palisades N. J., and Haverstraw, N. Y.," Muse. 

 App. 70. Sterile in our range. 



DICHODONTIUM Schimp. 



Plants cespitose or in loose mats. Leaves lingulate to linear- 

 lanceolate, widely spreading when wet, incurved to crispate 

 when dry; lower leaf cells elongate, upper roundish to quadrate, 

 more or less papillose both sides. Capsule cylindric to oblong, 

 erect and symmetric to cernuous and curved; peristome teeth 

 united below, more or less divided. 



