OF WESTERN PENNSYLVANIA 337 



late fall or winter, about .015-020 mm., the walls medium- 

 incrassate, brownish, and somewhat papillose: autoicous. 



On earth, stones, roots and bases of trees, rotten woodj 

 etc., in moist, shady woods; said to be especially common in 

 pine or hemlock woods; Europe, Asia, northern Africa, and 

 from Arctic America southward to South Carolina and Mis- 

 souri. Common in our region. 



Allegheny : Moon Township, 1888. J. A. S. ; on rotten 



log, Fern Hollow, Pittsburgh, January 21, 

 1906, Douthett, April 26, 1908 (Figured), 

 Guvasuta Hollow, Sharpsburg, November 

 9, 1908, and Keown, November 14, 1909. 

 O. E. J. 

 Butler : On humus under Pinus rigida, near Crider's 



Corners, December 29, 1908. O. E. J. 

 Crawford : Pymatuning Swamp, Linesville, August 



3, 1909. O. E. J. 

 Clinton : Between Renovo and Haneyville, July 15, 



1908. O. E. J. 

 Elk : McMinn., (Porter's Catalogue). 



McKean : Langmade, Bradford, April 25, 1897, and 



Marilla Brook, Bradford, September 20, 

 1897. D. A. B. 

 Westmoreland: Laurelville, May 30-31, 1903. J. A. S.; 

 Hillside, May 22, 1909. O. E. J. 



6. Brachythecium flexicaule Renauld and Cardot. 



(Plate L) 



Widely cespitose, yellowish-green : stems usually 3-6 

 cm. long, creeping, irregularly pinnate ; leaves plicate, erect- 

 spreading, the stem-leaves lanceloate, about 1.8-2.5x0.6-0.9 

 mm. ; branch-leaves narrower, up to 2.4x0.5-0.7 mm., 

 gradually slenderly acuminate from a deeply concave, some- 

 what decurrent plicate base with often narrowly reflexed basal 

 margins, the margins serrulate above ; costa extending to above 

 the middle of the leaf; median leaf-cells linear-fusiform, 

 prosenchymatous, flexuous, about 8-15 :1, rather incrassate, the 

 apical shorter, the ,basal rather abruptly shorter and wider with 

 two to four rows of large oblong to rounded-quadrate cells 

 across the whole median base, the alar cells sub-quadrate, 

 rather incrassate, numerous, the wings decurrent; perichaetial 

 leaves up to 3 mm. long with slender ftexuous acuminations, 

 partly sheathing, ecostate or nearly so: seta smooth, castane- 

 ous, usually sinistrorse, 1.5-2.5 cm. long; capsule oblong- 

 cylindric, inclined to nearly horizontal, dorsally gibbous, sub- 

 arcuate, pale-castaneous, slightly narrowed below the rim when 

 dry, the urn from 2-A mm. long; lid conic-acuminate, about 



