222 American Midland Naturalist Monograph No. 6 



5. Amblystegium trichopodium C. Hartman 



{Amblyslegium riparium var. trichopodium Bruch and Schimper; 

 Leptodictyum trichopodium Warnstorf) 



Loosely matted; stems 2-4 cm long; branches often ascending; stem-leaves 

 loosely to widely spreading, ovate to lance-ovate, abruptly long-acuminate, 

 about 1.5 mm long, plane, sometimes sub-serrulate; costa strong almost reach- 

 ing apex; median leaf -cells elongated hexagonal to rhomboidal, about 4:1, 

 rectangular to oblong at base; branch leaves smaller and more lanceolate: seta 

 about 3 cm long; capsule ovoid to somewhat cylindric, cemuous and curved; 

 peristome complete; spores ripe in spring. 



Frequent across northern North America, but not yet reported for our 

 region. 



6. Amblystegium Kochii Bryologia Europaea 



{Leptodictyum trichopodium var. Kochii (Bruch and Schimper) Brotherus) 



Plate XLII 



Stem prostrate with short erect or ascending branches, the branches not 

 usually reaching more than 5 or 6 mm long, the general color of the loose 

 mats being pale green to deep green: stem- and branch-leaves very similar, 

 spreading rather widely or almost squarrose, erect-spreading when dry, cordate- 

 ovate, narrowed but scarcely decurrent at base, the apex long and slenderly 

 acuminate, the leaves sometimes narrower and more lanceolate but always 

 long-acuminate, usually 1-1.5 mm long, entire to faintly serrulate, plane- 

 margined; costa medium strong, yellowish, usually about three-fourths as long 

 as the leaf; median leaf-cells more or less chlorophyllose, thick-walled, rhom- 

 boid-hexagonal, the ends blunt or parenchymatous, about 4-6:1 or longer, the 

 basal wider, the alar rectangular to rounded-quadrate, quite densely incras- 

 sate, hyaline or colored, but scarcely forming distinct alar patches; perichaetiai 

 leaves up to 2 mm long, lance-linear, long-acuminate: seta about 1.5-3 cm 

 long, castaneous, flexuous, dextrorse; capsule hypnoid, similar to that of A. 

 serpens, the urn oblong-cylindric, inclined to cernuous, arcuate, about 2-2.5 

 mm long, contracted below the mouth when dry; peristome-teeth brownish or 

 yellowish, hyaline and papillose above, cross-striolate below, hyaline-margined, 

 strongly and closely trabeculate, the dorsal lamellae and divisural plain; seg- 

 ments about as long as the teeth, slightly carinate, split, the basal membrane 

 about two- fifths as high; cilia usually 3, pale, papillose, some of them as lona 

 as the teeth, nodose; annulus rather large, two-seriate; upper exothecial cells 

 small, rounded-hexagonal or quadrate, below becoming elongate-hexagonal or 

 oblong-rectangular; spores in late spring or early summer, somewhat incrassate, 

 castaneous, minutely roughened, about .015-.018 mm. 



On moist earth in swampy or marshy places; Europe, Asia, and probably 

 throughout temperate North America. Fairly common in our region but in 

 its smaller sizes difficult to satisfactorily distinguish from A. ]iiratzk<inum. 

 Grout (Moss Flora) treats this as a variety of A. trichopodium. 



Now known from Allegheny, Centre, Crawford, Fayette, Lawrence, McKean, Wash- 

 ington, and Westmoreland counties. Sfsecimen figured: On root of black walnut, tree, 

 Hanlin. May 21, 1908. O.E.J. 



