272 American Midland Naturalist Monograph No. 6 



linear, flexuous, prosenchymatous, the basal somewhat larger but very similar, 

 a small group of short-rectangular or quadrate cells at the angles; costa none 

 or but very faint: capsule oval-oblong, cernuous, arcuate, plicate when dry 

 and then constricted below the mouth; peristome hypnoid, segments narrow, 

 cilia 2 or 3, about as long as the segments, unequal; annulus none; spores in 

 autumn, but capsules rarely produced. 



Over earth, stones, and rotten wood and humus, in woods; from Nova 

 Scotia to Manitoba and southward to Missouri and Tennessee. 



Rare in our region. McKean Co.: D. A. Burnett. Porter's Catalogue). Washing- 

 ton Co.: On rock, near Washington. December 5, 1891 (figured). A. Linn and J. S. 

 Simonton. 



4. IsoPTERYGiUM GEOPHILUM (Austin) Jaeger 



(Rhynchostegium geophilum Austin; Plagiothecium geophilum Grout; 

 Hypnum depressum Sullivant and Lesquereux) 



Plate LXVIII 



Dark green, very glossy, thinly, softly, and loosely matted, leafy branches 

 about 2.5-3 mm wide; stems prostrate, irregularly divided, more or less com- 

 pressed; leaves long, somewhat concave, distichous, rather distant, widely 

 spreading, ovate to oblong-lanceolate, gradually and symmetrically narrowed 

 to a somewhat blunt af>ex, serrulate above, rounded at the base, non-decurrent; 

 costa short, double, rather distinct or none; median leaf-cells linear, prosen- 

 chymatous, flexuous, about 8-12:1, a few alar sub-rectangular, thick-walled, 

 only a little enlarged and not forming a distinct auricle, upper cells shorter, 

 papillose dorsally by projecting cell-wall angles; many branches of our speci- 

 mens (July 26, 1947) were tipped with capitate clusters of linear, often forked 

 gemmae: capsule small, ovate, gibbous, thin-walled, unsymmetric, inclined; 

 urn about 1 mm long; peristome normally hypnoid, teeth yellowish, segments 

 narrow, linear, the cilia 2 or 3, some as long as segments; annulus large, 2- 

 seriate; lid conic, obliquely long-rostrate; spores mature in spring or summer. 



On moist earth or stones, usually near water in lowlands or in shady 

 ravines; occurring from New York to Wisconsin and south to Maryland and 

 Georgia. 



Cambria Co.: Cresson. T. C. Porter. (Porter's Catalogue). Somerset Co.: Becic 

 Spring, Laurel Ridge. C.M.B. July 26, 1947 (figured). 



5. IsoPTERYGiUM PULCHELLUM (Dickson) Jaeger 



(Plagiothecium pulchellum Bryologia Europaea; P. pseudo-latebricola 

 Kindberg; Leskea pulchella Hedwig) 



Slender, in prostrate and straggling tufts, bright glossy metallic green: 

 stems creeping, usually not much more than 1 cm long, the branches numer- 

 ous and slender, erect or curved-ascending; leaves subdistichous, about 1 mm 

 long, more or less falcate at tips of stems and branches, very glossy, hardly 

 altered when dry, entire, plane-margined, narrowly lance-ovate, from near the 

 base rounded but not decurrent nor excavate; costa usually none; median leaf- 

 cells narrowly linear, about 12 25:1, .0O5-.(X)8 mm wide, pointed, the basal 



