OF WESTERN PENNSYLVANIA 341 



McKean : On stones in running water, Langmade, 



Bradford, September 11, 1895. D. A. B. 

 Washington : Hanlin, May 21, 1908. O. E. J. 



10. Brachythecium reflexum [Starke] Bryologia Europaea. 

 (Hypnum reflexum Starke; H. subtenue James; Thuidium la.vi- 



foliuin Macoun). 



Very slender, dark green, densely intertwining to form 

 low, flat patches : the branches short, delicate, often curved, 

 more or less pinnately arranged ; stem-leaves cordate-triangu- 

 lar, quickly narrowed to a fine, long, often twisted acumen, 

 strongly decurrent, minvitely serrulate all around ; branch- 

 leaves narrower, cordate-ovate, strongly decurrent, serrulate all 

 around, smooth to faintly plicate, margins plane to very nar- 

 rowly recurved, when dry spreading" or imbricate and render- 

 ing the branches rather julaceous ; costa strong, reaching to 

 apex or even into the acumen ; leaf-cells short and broad, about 

 5-8:1, rhomboid-fusiform, sub-obtuse, rather incrassate, to- 

 wards the basal angles becoming gradually shorter and broader, 

 the alar large, pellucid, rounded-quadrate to rounded-rectangu- 

 lar, not forming very clearly distinct auricles: seta slender, 

 about 1-1.5 cm. long, rough ; capsule small, about 2 mm. long, 

 ovate-globose, curved, dorsally turgid, abruptly horizontal ; lid 

 coTivex-conic, apiculate ; arinulus narrow ; cilia slender and ap- 

 pendiculate; spores mature in winter :.autoicous. 



On rocks and tree-trunks in mountainous or hilly regions ; 

 Europe, Asia, and from Arctic America to Missouri and 

 Garrett County, Maryland (J. Donnell Smith). Rare in our 

 region. 



McKean : Bradford. D. A. Burnett. (Porter's Cata- 



logue). 



11. Brachythecium starkei [Bridel] Bryologia Europaea. 

 (Hypnum starkei Bridel). 

 (Plate LI) 

 Dark green, widely and thinly cespitose, the plants usual- 

 ly quite distinctly complanate : stems slender, creeping, radicu- 

 lose, pinnate with short, curved-ascending, rather distant, 

 slender branches ; branch-leaves loose, divergently spreading, 

 often somewhat secund, those from the middle of the branches 

 broadly ovate to broadly triangular-cordate, abruptly and 

 usually rather shortly slender-acuminate, apically twisted, rare- 

 ly plicate, strongly and broadly decurrent, marginally serrate 

 above, denticulate below ; costa variable but usually about 

 three-fourths as long as the leaf; median leaf-cells about 

 8-15:1, fusiform-hexagonal to fusiform-rhomboid, sometimes 

 shorter, somewhat incrassate; the basal in one or two rows 

 more or less rectangular-oblong, the alar rather numerous, sub- 



