Jennings: Manual of Mosses — 31. Hypnaceae 273 



suboval and wider and shorter but not differentiated otherwise at the angles: 

 monoicous; seta reddish, slender, about 1-1.5 cm long; capsule small, rather 

 variable, ranging from oblong and tapering below into the neck to short and 

 ovoid, and from erect and symmetric to curved and more or less horizontal, 

 when dry usually wide-mouthed and constricted below the rim, ranging from 

 greenish-brown when young to castaneous when old; lid conic, apiculate; peri- 

 stome-teeth densely barred, cilia 2, a little shorter than the segments; annulus 

 2-seriate; spores mature in early summer. 



On rocks and roots of trees and on rotten wood, in moist woods; Europe, 

 Asia, and from Arctic America to the northern United States as far south as 

 Pennsylvania. 



IsOPTERYGlUM PULCHELLUM var. NfTlDULUM (Wahlenberg) Brotherus 



(Hypnum nitidulum Wahlenberg) 



Larger plants in thinner mats, with often stoloniferous stems and more 

 complanate branches; leaves with very slender acuminations, often serrulate 

 above; capsule almost horizontal; annulus 1 -seriate often falling still attached 

 to the operculum. Range about the same as the species. 



Elk Co.: Benezette. McMinn. (Porter's Catalogue). 



6. IsOPTERYGlUM MICANS (Swartz) E. G. Britton 



(Hypnum albulum C. Mueller; H. micans Swartz; Sematophyllum micans 

 Braithwaite; Plagiothecium micans Paris) 



Small, thinly matted, loose, glossy, whitish-green to yellowish-green: stems 

 prostrate, rooting, irregularly branching; leaves loose, erect-spreading to secund 

 and pointing downwards, very small, about 0.8-1.2 mm long, ovate-lanceolate, 

 gradually long-acuminate, serrulate above, thin; costa usually none; perichaetial 

 leaves abniptly acuminate, the inner apically serrate; median leaf-cells linear, 

 prosenchymatous, flexuous, about 15:1, at the base a row considerably 

 enlarged and broad, at the angles a few sub-quadrate: seta long and slender; 

 capsule very small, ovate-oblong, light castaneous, constricted below the mouth 

 when dry and empty, slightly incurved; peristom.e-segments not split, about as 

 long as teeth, the cilia 1 or 2, short, nodose; annulus none; lid conic, apiculate 

 to short-rostrate; spores mature in mid-winter. 



On earth and rotten wood in moist woods; mainly along the eastern United 

 States from New York southwards. 



Rare in our region. Centre Co.: Bear Meadows. T. C. Porter. (Porter's Cata- 

 logue ) . 



7. IsOPTERYGlUM TURFACEUM (Lindberg) Lindberg 



{Hypnum turfaceum Lindberg; Stereodon turfaceuf Mitten; 

 Plagiothecium turfaceum Lindberg) 



Plate LI 



Small, light green to yellowish-green, loosely matted: stems prostrate, more 

 or less pinnately branching with short branches, rooting at the perichaetia and 



