Jennings: Manual of Mosses — 31. Hypnaceae 251 



5. Campylium radicale (Beauvois) Grout 



(Hypnum radicale Beauvois; H. bergenense Austin; 

 Amblystegium radicale Mitten) 



Plate XLII 



Loose, slender, pale-green, little branched, the branches often erect and up 

 to 2 cm or more long; branch-leaves distant, more or less widely spreading, 

 lanceolate- to ovate-cordate, up to 1.5x0.7 mm, concave at base, entire or 

 almost so, dccurrent, abruptly slenderly acuminate and somewhat channelled; 

 m.edian leaf -cells about 4-8:1, sometimes longer, medium-walled, the alar some- 

 times more abruptly enlarged and hyaline; costa well developed, orange, up to 

 two-thirds or three fourths as long as the leaf; perichaetial leaves slenderly 

 acuminate and up to 2.5 mm long, plicate, erect: seta up to 3 cm long, cas- 

 taneous, strong, dextrorse; capsule yellowish, the urn about 2.7 mm long, 

 arcuate, oblong-cylindric, contracted below the mouth when dry; peristome- 

 teeth strong, castaneous, strongly trabeculate, hyaline-margined, the dorsal 

 lamellae cross-striolate below, papillose and hyaline above; segments entire or 

 nearly so, about as long as teeth, the basal membrane about two-fifths as high 

 as teeth; cilia 2 or 3, usually one, at least, as long as the segments, nodose, 

 hyaline, minutely papillose, medium-walled, about .016-.019 mm, mature in 

 spring. 



On rotten logs, roots of trees, wet soil, etc., in wet, sh.qded places: Europe, 



Asia, and apparently well distributed throughout temperate North America. 



The species occurs in eastern Pennsylvania and has been found twice in our region. 

 Butler Co.: West Liberty Bog. C.M.B. Aug. 29, 1931. McKean Co.: In springy 

 places near Bradford, May 17, 1895. D.A.B. (figured). 



13. Ctenidium (Schimper) Mitten 



Usually dioicous, mostly slender, soft, cespitose, green to yellowish or 

 golden-brown, lustrous: stem long, here and there with clusters of rhizoids, 

 more or less regularly pinnate, branches short and mostly horizontally spread- 

 ing; leaves falcate to circinate-secund, decurrent, more or less plicate, mostly 

 abruptly lance-subulate from a broadly cordate base, serrate (C. procerrimum 

 is entire) ; costa double and very short or none; cells narrowly linear, the upper 

 angle usually ending in a forward-projecting papilla, the alar cells distinct, 

 quadrate and rectangular, the angles sometimes weakly e.xcavate; branch-leaves 

 smaller: seta 1-2.5 cm long, red, smooth or nearly so; capsule inclined to 

 nearly horizontal, thickly oval, dorsally gibbous, not constricted below the 

 mouth; annulus broad, revoluble; peristome normally hypnoid; lid long-conic, 

 acute or obtuse; calyptra mostly more or less hairy. 



A genus of 30 species occurring mainly on trees and rocks in temperate 

 and warm regions; 4 species in North America, the following species in our 

 range. 



1. Ctenidium molluscum [Hedwig] Mitten 



{Hypnum molluscum Hedwig; H. compressum Roth) 

 Plate XL VI 

 Very densely cespitose, soft, lustrous, golden-green, rather robust: stems 



