OF WESTERN PENNSYLVANIA 295 



ing, closely regularly pinnate, plumose ; leaves densely im- 

 bricated, falcate-secund to circinate, stem-leaves 1.8-2.5 mm. 

 long, when dry usually plicate, and, especially towards the 

 points, more or less undulate and crisped, from a cordate-tri- 

 angular, concave, and auriculate base rather abruptly and 

 slenderly long-acuminate, plane-margined, strongly serrate, es- 

 pecially at the base, somewhat decurrent ; costa very short and 

 double or none; median leaf-cells about 8-15:1, the corners 

 somewhat projecting dorsally, gradually towards the angles 

 becoming irregularly quadrate-hexagonal, shorter and wider, 

 pellucid, forming poorly defined auricles of about the same 

 color as the rest of the leaf ; branch-leaves considerably smaller 

 and narrower, not cordate-auriculate ; perichaetial leaves slen- 

 derly lance-acuminate; paraphyllia ovate, mostly at the base 

 of the branches: seta brownish, flexuous, slender, about 1.0-2.5 

 cm. long, castaneous; capsule-urn about 2.5 mm. long, oblong 

 to oval, slightly curved to almost straight, from the curved 

 apex of the seta mostly horizontal, not constricted below the 

 mouth when dry ; lid conic-acuminate ; annulus broad ; peris- 

 tome normally hypnoid, teeth yellowish, segments carinately 

 cleft, about as long as teeth, the cilia 2 or 3, stout, about as 

 lon as the segments, the basal membrane about one-half the 



o o 



height of the peristome ; calyptra somewhat hairy when young; 

 spores mature in summer, smooth, yellowish-incrassate, about 

 .015-.018 mm. 



On moist, shaded earth and rocks in w r oods in hilly or 

 mountainous districts ; Europe, Asia, northern Africa, and from 

 Newfoundland to the Rocky Mountains and south to Georgia. 

 Rather common in our region. 



Blair : A. P. Garber. (Porter's Catalogue). 



Cambria : Cresson. T. C. Porter. (Porter's Cata- 



logue ). 



Elk : McMinn. (Porter's Catalogue). 



McKean : On rich, shaded bank of stream, Lang- 



made, April 3. 1897, and April 25, 1897. 

 (Figured), and on rocks bordering rivu- 

 lets, head of Gates' Hollow, Bradford, Oc- 

 tober 27. 1895. D. A. B. 



\Yashington : Linn and Simonton. ( Porter's Catalogue). 



12. RHYTIDJJDELPHUS (Lindberg) Warnstorf. 



Dioicous : more or, less robust, stiff, loosely cespitose 

 forming loose, wide, stiff, green to yellowish or grayish, and 

 rather lustrous mats ; stem angled, long, without rhizoids, 

 simple to regularly or irregularly pinnate ; branches partly 

 short and obtuse, partly long and acuminate, and often curved 

 above ; upper half of the leaf spreading-squarrose to reflexed- 



