OF WESTERN PEXXSYLVAXIA 119 



2. Orthotrichum lescurii Austin. 



(O. cupulaium variety minus Sullivant). 



(Plate XV) 



Rather densely cespitose, about 5 mm. high : stems thickly- 

 foliate, branched ; leaves lanceolate or some of the lower ovate, 

 the upper about 3 mm. long, the lower shorter, acute, the mar- 

 gins entire, revolute, strongly costate nearly to the apex; basal 

 leaf-cells quadrate to elongate-rectangular, smooth, hyaline,, 

 above becoming rounded-hexagonal, sub-opaque, densely 

 papillose, smaller and quite regularly hexagonal at the apex; 

 seta very short, 0.5 mm., about one-half enclosed in the in- 

 volucre ; calyptra narrowly campanulate, plicate, hirsute with 

 erect hairs : lid mamillate, rounded but flattened : capsule ob- 

 long-cylindric and rather suddenly tapering to the seta, about 

 1.3 mm. high and 0.5 mm. in thickness, when moist globose- 

 oblong and S-striate, when dry deeply 8-furrowed and some- 

 times contracted below the mouth ; capsule always about the 

 same length as the upper leaves, or sometimes slightly exserted 

 when dry ; peristome single, the teeth 8, short, equid'istant but 

 leaning towards each other in pairs, triangular-lanceolate, 

 papillose, articulate, the divisural usually complete and not 

 split, teeth when dry erect or incurved ; spores mature in 

 spring, .014-.017 mm. 



On rocks, usually granite or trap ; from New England to 

 Ontario south to Missouri and Pennsylvania, and in the Rocky 

 Mountains to British Columbia. Rare in our region. 



Westmoreland : On sandstone rocks at mouth of Bear's 



Cave, on slope of Chestnut Ridge above 

 Hillside, September 16, 1910. O. E. J. 

 and G. K. J. (Figured). 



3. Orthotrichum braunii Bryologise Europse. 

 ( O. strangulatum Sullivant). 



(Plate XV) 



Sparsely cespitose to scattered, less than 5 mm. high, dark 

 green : stems sometimes creeping at base, erect-spreading, 

 simple or branched ; leaves spreading when moist, the upper 

 somewhat clasping, when dry appressed, not crisped, concave, 

 ovate to lance-ovate, the margins more or less revolute, apex 

 acute, sometimes erose-denticulate and apiculate and some- 

 times hyaline ; costa strong, sub-percurrent basal leaf-cells hya- 

 line, smooth, at margin quadrate, about .016 mm. in diameter, 

 toward the costa rectangular and reaching about .090X-016 

 mm., median cells papillose, opaque, rounded, about .020 mm. 

 in diameter, the apical smaller, rounded and less papillose; 

 capsule oblong-oval, about 1.2 mm. long tapering abruptly into 

 a seta about one-third as long, 8-costate, when dry much con- 



