56 American Midland Naturalist Monograph No. 6 



the end-walls thinner than the lateral walls, two to four rows of cells at the 

 rim much smaller and rounded; spores .010-.015 mm, yellowish-incrassate, 

 mature in autumn. 



Common, especially in hilly or mountainous districts, on rocks, clay banks, 

 soil-covered logs, etc. Europe, Asia, and, in North America, from Canada 

 to the Gulf States. 



A very common moss on soil in the southwestern part of the State from Erie to 

 eastern Somerset and Greene counties (13 counties ) but as yet known only from Cam- 

 eron and Centre counties on the elevated plateaus and mountains. Specimen figured: 

 "Rachelwood," slope of Laurel Ridge, southeast of New Florence. Sept. 8-11, 1907, 

 O.E.J. 



3. DiCRANELLA RUFESCENS [Dickson] Schimper 



Plates XI and LX 



Rather loosely cespitose, reddish- to yellowish-green: stems erect, in our 

 region generally very short, reddish, about 3 mm or less high, mostly simple; 

 leaves few, linear-lanceolate, sometimes reaching 1.5 mm long, gradually nar- 

 rowed, minutely denticulate towards apex, plane, erect-spreading or sometimes 

 sub-secund; costa narrow, about one-seventh to one fifth the width of the leaf- 

 base, percurrent; basal leaf-cells large, hyaline, smooth, thin-walled, quadrate- 

 rectangular to linear-rectangular, reaching 8-10 times as long as wide, median 

 cells shorter and smaller but similar, the percurrent costa margined by cells 

 similar to the median: seta erect, red, about 3-5 mm long, dextrorse when dry; 

 capsule globose-ovoid, erect, red, symmetrical, smooth to slightly wrinkled 

 when dry, the urn wide-mouthed and more or less turbinate; operculum 

 obliquely conic-rostrate, nearly as long as urn (0.5 mm) ; calyptra cucullate, 

 smooth, yellowish-red, narrowly conic, about 0.8 mm long; peristome pellucid 

 red-chestnut in color; teeth bifid about half-way, articulate, irregularly and 

 finely longitudinally striate-papillose; spores globose, smooth, orange-pellucid, 

 about .012-. 01 5 mm, mature in late summer or fall. 



Usually on damp, bare soil, in Europe, Asia, and, in North America, from 

 Alaska to Nova Scotia and southwards to Virginia. 



Rather common in our region. Now known from the following, counties: Allegheny, 

 Beaver, Butler, Cambria (Porter), Elk (Porter), Fayette, Huntingdon (Porter), Indiana, 

 McKean. Specimen figured: Clay soil on upper slope 'of Laurel Mt., above New Flor- 

 ence, Sept. 8-11, 1907. O.E.J. ; and for the perigonial shoots, clay bank of ditch, Elder's 

 Ridge, O.E.J. & G.K.J. Nov. 2, 1941. 



4. DiCRANELLA VARIA [Hedwig] Schimper 

 Plate XI 

 Densely gregarious to cespitose, bright to yellowish-green; stems short, 

 usually about 5-7 mm high, ascending to erect, branching at base; leaves up to 

 2.5 mm long, linear-lanceolate, gradually narrowed to a long-linear acumina- 

 tion, spreading to recurved, not very secund, when dry somewhat flexuous, 

 margin narrowly revolute, entire, excepting sometimes at the very apex some- 

 what denticulate; costa wide and not well-delined, percurrent and comprising 

 a large portion of the acumen; basal leaf-cells rather thin-walled, rectangular or 

 with oblique end-walls, 2-6:1, gradually becoming smaller and narrov.'er above, 



