Jennings: Manual of Mosses — 34. Brachytheciaceae 301 



1. OxYRHYNCHiUM RiPARioiDES [Hedwig] Jennings 



(Hypnum ntfciforme Necker; Emyncbium rusciforme Milde; Hypiium 

 riparioides Hedwig; Rhynchostegium rusciforme Bryologia Europaea ) 



Plate LVIII 



Robust, in large tufts, dark to blackish below: stems prostrate, woody, and 

 usually denuded below; branches suberect, or ascending, usually more or less 

 rigid and harsh, especially when dry; leaves ovate, loosely ascending or erect- 

 spreading, scarcely decurrent, about 2-2.5x1.5 mm, obtuse to acute, plane- 

 margined, denticulate nearly to the base; costa thick below, reaching to one- 

 half or two-thirds the length of the leaf, or occasionally even sub-percurrent, 

 often ending in a dorsal spine; median leaf-cells incrassate, linear-fusiform, 

 about 10-12:1, the apical and basal shorter and broader, but no alar group 

 differentiated, the median and upper slightly dorsally spinose- seta smooth, 

 about 1.5 cm long, castaneous, slightly twisted when dry; capsule castaneous, 

 ovoid-oblong, somewhat constricted below the mouth when dry, about 2-3:1, 

 dorsally turgid but scarcely curved, inclined or nearly horizontal, the urn about 

 1.5-2 mm long; lid obliquely slenderly rostrate from a conic base, about two- 

 thirds as long as the urn; annulus revoluble, usually 2-seriate; exothecial cells 

 vellowish-incrassate, at the rim small and rounded-quadrate, below rather large 

 and irregularly oblong-rectangular; peristome-teeth slender, apically hyaline- 

 papillose, strongly trabeculate, dorsally plainly lamellate and finely cross- 

 Jtriolate, margined, confluent at base; segments about as long, usually carinate- 

 ly widely gaping but remaining unsplit at apex, the basal membrane about one- 

 half as high; cilia 2-3, subulate, nodose to sub-appendiculate, somewhat shorter 

 than the segments; spores weakly papillose, medium-walled, yellowish, about 

 .010-. 01 3 mm, mature in early fall. 



On wet or submerged rocks in streams and rivulets; Europe, Asia, northern 

 Africa, and from Newfoundland to Ontario and southwards in the mountains 

 to Georgia. 



Common in our region. Now known from the following counties: Armstron'^, Bed- 

 ford, Butler, Cambria (Porter), Cameron, Centre, Fayette, Lawrence, McKean, Somer- 

 set, Warren, Washington, and Westmoreland. Specimen figured: Rachelwood, Mellon's 

 Estate near New Florence, Laurel Hill Mts., Westmoreland Co., Sept. 8-11, 1907. 

 O.E.J. 



2. OXYRHYNCHIUM HIANS (Hedwig) Jennings 



(Hypnum hians Hedwig; Eurynchium htans Jaeger and Sauerbeck; Hypnum 

 praelongum C. Mueller; Pterygynandrum apiculatum Bridel ) 



Plate LVIII 



Rather slender, depressed, cespitose, somewhat shining: stems creeping, 

 rather sparsely branched, slender, usually not over 3 or 4 cm long, the branches 

 short and more or less distichouslv arranged; leaves of the stem and longer 

 branches rather distant, on some of the short branches sometimes more or less 

 imbricated-julaceous, the stem-leaves about 1-1.6 mm long by three-fourths as 

 wide, ovate, the apex abruptly acute to shortly acuminate, the base clasping 

 but not decurrent, margins sharply serrulate nearly to the base; branch-leaves 



