302 A MANUAL OF MOSSES 



Clinton : Between Renovo and Haneyville, July 15, 



1908. O. E. J. 



Elk : McMinn. (Porter's Catalogue). 



McKean : In thin mats on perpendicular face of 



sandstone rocks at head of Rutherford 

 Run, altitude 1800-2000 feet, April 25, 

 1895, and on densely shaded rocks along 

 Marilla Brook, one-half mile above reser- 

 voir, Bradford. D. A. B. The latter is- 

 sued as Grout's No. 44a, Noi-th American 

 Musci Pleurocarpi. (Figured). 



Washington : Linn and Simonton. (Porter's Catalogue). 



15. HYPNUM Linnaeus, Hedwig. 



Dioicous : robust, stiff, deeply and loosely cespitose, dark 

 to pale green or almost straw-colored, more or less lustrous : 

 from a decumbent base ascending to erect, with straight 

 pointed ends and rather regularly pinnate; branches mostly 

 spreading and 2-seriate, usually slenderly attenuate, sometimes 

 thick and obtuse ; no paraphyllia ; leaves crowded, imbricately 

 appressed, spoon-shaped, more or less distinctly plicate, scarce- 

 ly decurrent, broadly ovate to ovate-oblong, apex blunt, the 

 margin often narrowly revolute below and broadly involute 

 upwards, at the very apex only weakly crenulate or serrulate; 

 costa indistinct, or very thin, short and double; median leaf- 

 cells narrowly prosenchymatous, smooth, the basal shorter, 

 laxer, porose, incrassate, yellowsih to orange-red, the alar 

 abruptly enlarged, quadrate to shortly rectangular, or several- 

 angled, incrassate, colored, the alas more or less excavate ; peri- 

 chsetial leaves sheathing, lance-oblong, rather abruptly acumi- 

 nate, indistinctly costate : seta 2-4 cm. long, sinistrorse, tortu- 

 ous, yellowish-red to red; capsule cernuous, 2-2.5 mm. long, 

 usually horizontal, symmetric, or dorsally somewhat gibbous, 

 drying arcuate, slightly constricted below the mouth, brownish, 

 smooth ; annulus none ; lid high-convex, acute or conic-obtuse. 



The genus as here restricted contains only the following 

 species : 



1. Hypnum schreberi Willdenow, Schwaegrichen. 



(H. parietinum Linnaeus; H. muticuin Swartz; Stereodon schre- 

 beri Mitten; Hylocomium parietinum Lindberg). 



(Plate XLIV) 

 Usually bright yellowish-green: stems up to 12 or 15 cm. 

 long, bright red; stem-leaves 1.5-2.5 mm. long; median leaf- 

 cells about 10-15:1, the apical shorter: capsules produced 

 rather infrequently ; exothecial cells transversely oblong-hexa- 

 gonal, laterally strongly castaneous-incrassate ; peristome- 



