294 A MANUAL Oi- MOSSES 



leaves rather incrassate and blunt at the ends, the basal often 

 porose, the alar sub-rectangular, incrassale, rather opaque, 

 usualh' more or less orange-pellucid, forming distinct, often 

 somewhat decurrent auricles: seta rather long, castaneous, up 

 to 4.5 cm. long, stout, dextrorse above, flexuous ; capsule ob- 

 long-cylindric, about 3-4.5:1, arcuate, the urn 2-2.5 mm. long, 

 inclined to horizontal, sulcate and constricted below the mouth 

 when dry and empty, brownish; lid highly convex-acuminate: 

 annulus 2-3-seriate ; peristome normally hypnoid, large, the 

 teeth trabeculate, confluent at base, the lower part orange- 

 colored and dorsally cross-striolate, the lamellae and divisural 

 distinct, the upper part paler and papillose ; segments some- 

 what shorter and slightly carinately split: cilia 2 (or 3). nodose, 

 about as long as the segments ; spores mature in summer, 

 minutely papillose, rather thin-walled, pale yellowish, .011- 

 .014 mm. 



On wet banks in swamps ; Europe. Asia, and from Arctic 

 America southwards to Virginia. Rare in our region. 



Erie : Presque Isle, May 8-9, 1906. O. E. J. 



(Figured). 



McKean : D. A. B. (Porter's Catalogue). 



11. CTENlDll'M (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 spreading; leaves 

 spreading or circinate-secund, decurrent, non-plicate to weakly 

 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 ex- 

 cavate; 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 21 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. 



(Hypnwm molluscum Hedwig; H. co-mprcssnr.i Roth). 



(Plate XLII) 



Very densely cespitose, soft, lustrous, golden green, rather 

 robust : stems reaching 10 cm. in length, prostrate or ascend- 



