130 American Midland Naturalist Monograph No. 6 



decurrent, crisped and curled when dry, entire, obovate to sub-orbicular, with 

 a narrow base; costa slender and banishing below the apex; cells wide, thin- 

 walled, towards edge forming an indistinct margin: dioiccus: seta short; cap- 

 sule short-pyriform with wide mouth. A very distinct species on account of 

 the leaf characters. 



Wet places, Eurasia; and from Arctic America south to Pennsylvania, 

 New Jersey, and northwest. Not yet reported from our region. 



4. Bryum cuspidatum Schimper 



(B. affine Lindberg)* 



Plate XXIII 



Rather densely cespitose, becoming dark green: stem short, in ours usually 

 1-2 cm, occasionally longer, with slender innovations, somewhat matted with 

 a brownish tomentum, dark brown; leaves rather numerous, somewhat clasping 

 and short-decurrent, the margins revolute to near the apex where the leaves 

 are slenderly acuminate and more or less serrulate, the leaves ranging from 

 oblong-lanceolate below to elongate ovate-lanceolate above and on the branches; 

 when dry the leaves are moderately shrunken and twisted; costa strong, reddish, 

 long-excurrent; leaf-cells rhomboid-hexagonal above, to thin-walled, reddish, 

 and more or less inflated-rectangular at the base, the marginal in two to five 

 rows of linear-prosenchymatous more or less yellowish-pellucid cells forming 

 a strongly marked border: seta slender, flexuous, lustrous-castaneous, about 

 2-4.5 cm in height; capsule about 3 mm long, elongate oblong-pyriform, with 

 a tapering neck a little shorter than the rest of the capsule, yellowish-brown, 

 finely deep brown, when dry and empty constricted below the deeper-colored 

 mouth, more or less pendulous; operculum wide, convex, mamillate; annulus 

 wide, revoluble; peristome-teeth linear-triangular, yellowish-pellucid below, sub- 

 hyaline and papillose ^bove, strongly trabeculate, lamellate, the zig-zag divis- 

 ural usually distinct: basal membrane of inner peristome about half the length 

 of the teeth, the segments carinately split, hyaline and papillose, a little shorter 

 than the teeth, the three filiform, appendiculate cilia somewhat shorter than the 

 segments; spores yellowish-pellucid, minutely roughened, usually about .010- 

 .014 mm; exothecial cells irregularly quadrate to rectangular-hexagonal, incras- 

 sate, three or four rows below the mouth being much smaller, rounded-quad- 

 rate and reddish-pellucid; synoicous: spores mature in summer. 



Usually on or between wet rocks. Widely distributed in Europe, Asia, and 

 northern North America. 



Known from the following counties: Allegheny, Beaver, Cambria, Erie, Fayette, Law- 

 rence, McKean, Somerset, and Westmoreland. Specimen figured: Presque Isle, Erie Co., 

 May 8-9, 1906. O.E.J, (figured). 



5. Bryum pallescens [Schleicher] Schwaegrichen 

 Plate XXIII 



Sub-cespitose, yellowish-green: stems short, 4-9 mm, sparsely branching, 

 reddish, somewhat reddish-tomentose below, erect; leaves small and remote 



* Also B. intermedium of the first edition of this Manual, B. intermedium being an 



