OF WESTERN PENNSYLVANIA 269 



similar, the basal tending- to sub-quadrate or shortly rectangu- 

 lar, the alar forming a rather distinct group, sub-pellucid, 2-3 

 times as wide as the median cells, decidedly incrassate, and al- 

 ways as long or longer than wide, perichsetial leaves 1.5-2 mm. 

 long, acuminate, thin, plicate: seta castaneous, smooth, about 

 2-2.5 cm. high, when dry flattened, flexuous, dextrorse ; capsule 

 unsymmetric, cernuous, decidedly arcuate, often describing a 

 half-circle, about 1.5-2.0 mm. long, smooth, reddish, when dry 

 and empty much contracted below the wide mouth ; peristome 

 typically hypnoid; teeth reddish, pellucid, strongly articulate 

 and trabeculate, confluent slightly at base, hyaline-margined, 

 divisural zigzag, dorsal cross-striae evident ; segments as long 

 as the teeth, sub-entire, reddish-yellow, carinate, not at all or 

 but slightly split, cilia 1-3, of equal length, or some shorter, 

 nodose, united a little below the middle with the segments to 

 form the basal membrane ; spores rather clear, minutely papil- 

 lose, medium to rather thin-walled, mature in spring, .010-012 

 mm. in diameter. 



On moist soil and stones ; Europe, Asia, and, in North 

 Ahierica, from Canada to the Gulf of Mexico. Rather common 

 in our region. This species is intermediate between A. serpens and 

 A. kochii, but from the former differs in the more squarrose- 

 spreading leaves, longer alar cells, and stronger costa, while 

 from the latter it differs mainly in smaller size and longer-pointed 

 leaves. 



Allegheny : Douthett, June 5, 1909, Fern Hollow, 

 Pittsburgh, April 25, 1909, Power's Run, 

 May 7, 1905, Nine-Mile Run, May 17, 1907. 

 O E. J. ; Moon Township, May 18, 1902. 

 and Laschell Hollow, June 15, 1902. 

 J. A. S. 



Crawford : Linesville, in Pymatuning Swamp, June 



11-12, 1907, and May 12, 1908. O. E. J. 

 (Figured). 



Erie : Presque Isle, June 9-11, 1905. O. E. J. 



Fayette : Ohio Pyle, September 1-3, 1906. O. E. J. 



5. Amblystegium radicale [Beauvois] Mitten. 



{Hypmun radicale Beauvois; H. bergenense Austin; Campylium 

 radicale Grout). 



(Plate XXXVIII) 



Loose, slender, pale-green, little branched, the branches 

 often erect and up to 2 cm. or more long ; branch-leaves distant, 

 spreading to somewhat squarrose, lanceolate- to ovate-cordate, 

 up to 1.5X0.7 mm., concave at base, entire or almost so, de- 

 current, abruptly slenderly acuminate ; median leaf-cells about 

 4-8:1, sometimes longer, medium-walled, the alar sometimes 



