Jennings: Manual of Mosses — 2. Dicranaceae 57 



the upper being about 2-4:1 and somewhat incrassate, all smooth and more or 

 less yellowish-pellucid: seta yeIlowish-brov»n to castaneous, ascending to erect, 

 about 5-8 mm long, sinistrorse; capsule ovate to oblong, more or less cemuous, 

 reddish to pale castaneous, curved, smooth, together with lid about 1-1.25 mm 

 long; lid about as long as urn, rostellate; peristome-teeth large, lance-subulate, 

 cleft to middle, strongly articulate, finely striate-papillose, rich castaneous 

 below, sub-hyaline above; spores yellowish, rather thick-walled, minutely rough- 

 ened, .020-. 024 mm, mature in late autumn or in winter. 



On bare clay soil in fields, on ledges, etc. Widely distributed in the 

 Northern Hemisphere; in North America from Nova Scotia to Alaska and 

 south to Georgia and the subtropics. 



Allegheny Co.: In niches on clifF, Powers Run, November 30, 1909 (figured). 

 O.E.J. Butler Co.: On moist shale in railroad cut, Wahlville. Sept. 22, 1935. Sidney 

 K. Eastwood. McKean Co.: Bennett Brook, October 23, 1897. D.A.B. Washington 

 Co.: On shale npar creek, west of Tayiortown. Nov. 5, 1892. A. Linn and J. S. 

 Simonton. 



8. Rhabdoweisia Bryologia Europaea 



Autoicous: low, densely cespitose: stem without central saand, in cioss- 

 section obtusely pentagonal, densely foliate, radiculose, branched; leaves v/hen 

 dry crisped, decurrent, linear to linear lanceolate, acute, plane-m.argined; costa 

 strong, disappearing below the apex; upper leaf-cells chlorophyllcse, quadrate 

 to rounded, smooth; basal cells rectangular and hyaline: S2ta straw-yellow, 

 erect; capsule erect, minute, symmetric, ovate to oblong, obtusely octagonal 

 with darker stride, 8-costate v/hen dry; annuli:s none; peristome rarely absent, 

 inserted on the rim; teeth arisina from lov/, broad, more or less united bases, 

 abruptly filiform or subulate, reddish-ye'Jow, trabeculr; prominent ventrally but 

 articulations scarcely projecting dorsally, surface of teeth non-papillose but 

 often obliquely minutely striate; operculum long-subu!ate, obliquely rostrate, 

 as long or longer than the urn; calyptra cucuUate, rostrate, reaching to the 

 middle of the capsule. 



About 8 species of the Northern Hemisphere, inhabiting crevices of 

 silicious rocks; 5 species in North America; 2 species in cur region. 



Key to the Species 



A. Leaves entire or nearly so L R. der.tkulata 



A. Leaves rather coarsely denticulate towards the apex 2. R. denticulata var. americana 



1. Rhabdoweisia denticulata (Bridel) Bryologia Europcca 



{Weisia fugax Am. Auth.) 



Plate XI 



Densely cespitose, usually dark green: stems short, in ours about 5 mm 

 high, radiculose at base; leaves lance-linear, recurved-spreading, numerous, 

 about 2-2.5 mm. long, usually somev/hat concave, acute to shortly acuminate, 

 margins plane, somewhat denticulate towards apex, leaves crisped when dry; 

 costa strong but not quite reaching apex; upper leaf-cells rounded-hevagonal, 

 about .010-. 014 mm, incrassate, chlorophyllose, papillose, rather yellow, ar- 



