124 American Midland Naturalist Monograph No. 6 



often reddish: seta long; capsule oblong, with inconspicuous neck, often unsym- 

 metric. mostly horizontal, castaneous or red-brown, when dry and empty 

 ventricose at base and constricted at the mouth; operculum conic-apiculate; 

 peristome yellowish, basal m.embrane not more than one-third as high as teeth, 

 rilia two or three, well-developed; usually autoicous, sometimes synoicous or 

 dioicous: spcres mature in summer. 



On shaded earth, clefts in rocks, etc., usually in mountainous regions. 

 Cosmopolitan but local in its distribution. In North America it etxends from 

 North Carolina and Tennessee to the far North. In our region rare, being 

 unknown from western Pennsylvania, but reported from the eastern part of 

 Pennsylvania and from Painesville, northeastern Ohio. 



3. POHLIA NUTANS [Schreber] Lindberg 



{Webera nutans Hedwig) 



Plate XXI 



More or less densely cespitose, usually dark green: stems about 1-2 cm 

 high, branching by lateral innovations, or from the, base, erect, matted with a 

 castaneous tomentum below, reddish; leaves ovate below to much longer and 

 linear-lanceolate in the comal tuft, hardly decurrent, the comal long-acumi.iate, 

 the margin often somewhat recurved below, denticulate towards apex, leaves 

 somewhat shrunken, twisted and lustrous when dry; costa strong, reddish, 

 ending in or a little below apex; leaf -cells long-rhomboid and more or less 

 pointed and prosenchymatoiis above, rectangular below, slightly narrower 

 towards the margin: seta slender, flexuous, usually 2-3 cm long, lustrous, 

 castaneous below, often yellowish above; capsule horizontal to sub-pendulous, 

 oblong to obovate, usually about 3-4 mm in length, with a distinct but short 

 neck, often gibbous when dry and then contracted below the wide mouth, 

 yellowish to brown in age; operculum convex-mammillate; peristome-teeth orange- 

 yellow below, paler and papillose in the rather abruptly narrowed upper half, 

 strongly trabeculate, lamellate, divisural zigzag and distinct; segments about 

 as long, carinately split and gaping below but remaining unsplit at apex; cilia 

 nearly as long, two in number, filiform, articulate, basal membrane half as 

 high as teeth; annulus wide, revoluble; spores smoothish, yellowish-pellucid, 

 about .014-.016 mm, mature in early summ.er: autoicous; antheridia in axils 

 of upper leaves. 



On various habitats in moist pbces or swampy fields and woods. Common 

 and nearly cosmopolitan. 



This species is now known from the following counties: Allegheny, Armstrong, Beaver, 

 Cambria, Centre, Crawford, Erie, Fayette, Indiana, Lawrence, Mercer, Montour, McKean, 

 Somerset, Washington, and Westmoreland counties. Specimen figured: Presque Isle, Erie 

 County, May 8-9, 1906. O.E.J. 



3a. Pohlia nutans var. triciliata New Combination 



{W. nutans var. triciliata Jennings) 

 Plate XXII 

 Plants laxly to densely cespitose, shining, dark green to yellowish: stem 

 simple or sparsely branched, erect, castaneous, at the base reddish-radiculose, 



