OF WESTERN PENNSYLVANIA. 61 



above; capsule erect, symmetric, about .6-.9X-2S-.3 mm,, ob- 

 long, not constricted below mouth, smooth or nearly so even 

 when dry and empty, when ripe brown; peristome single, the 

 teeth very slightly united below, cleft about half-way into 

 linear-subulate prongs, sometimes sub-cribrose along the di- 

 visural, articulate, longitudinally striolate-granulose, towards 

 apex hyaline; spores, minutely papillose, about .014— .017 mm., 

 mature in late fall or winter; operculum low-conic with an 

 oblique rostrum. 



On soil, soil-covered rocks, etc., in the eastern and south- 

 eastern parts of the United States. Not rare in our region. 

 Allegheny : Schenley Park, Pittsburgh, August 16, 1905, 



McKees Rocks, August 27, 1905, and Fern 



Hollow, Pittsburgh, March 8, 1908. (Figured). 



O. E. J. ; Wildwood Road, March 29, 1908. O. 



E. J. and G. K. J. 



2. Dicranella heteromalla [Dillenius] Schimper. 



(Dicraniim heteromallum Hedwig). 



(Plate VII) 



Cespitose, bright yellowish to dark green ; stem erect or 

 ascending, 0.5-3.0 cm. tall : leaves numerous, lance-subulate, 

 concave, 2-3 mm. long, denticulate towards the apex, usually 

 also denticulate dorsally towards the apex; costa strong, one- 

 fifth to one-third the width of the leaf at base, percurrent, 

 bordered towards the apex by a narrow margin of lamina ; leaf- 

 cells parenchymatous, at leaf-base 2-5 times as long as wide, 

 rectangular, brownish, narrower towards the margin, the upper 

 cells shorter and often obliquely quadrilateral; seta 1.5-2.5 

 cm. long, greenish-yellow, dextrorse; capsule smooth, abovit 1.5 

 mm. long, oblong, castaneous to dark brown, more or less 

 erect, usually slightly curved, when dry bent and curved in 

 at the upper part just below the rim on one side in a very 

 characteristic manner, furrowed ; operculum hemispheric, with 

 a linear obliquely inclined beak about 1 mm. long ; peristome- 

 teeth red, bifid to below the middle or about to the middle, 

 sometimes trifid, with somewhat projecting trabeculae, articu- 

 late, minutely papillose-striate, hyaline and papillose at apex; 

 exothecial cells incrassate, irregularly elongate-rectangular to 

 oblong-hexagonal, the end-walls thinner than the lateral walls, 

 two to four rows of cells at the rim much smaller and 

 rounded; spores .010-.014 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 lower Canada to the Gulf States. One of 

 the most common mosses in our region. 



