Jennings: Manual of Mosses — 22. Polytrichaceae 161 



fruit in our region, but has seta 15-20 mm tall; capsule terete, more or less 

 erect, with urn 2-3.5 mm long, about 3-4:1, lid with beak half as long as urn. 



Stream banks or other moist situations; N.E. to Ontario and Tennessee; 

 also in the Northwest. 



Butler Co.: On ground in wet ditch, Semiconon Run, lYi mi. north of Conoquenes- 

 sing. Sidney K. Eastwood. Sept. 22, 1935. Fayette Co.: Partly buried in sand around 

 banks of river, around "Peninsula," Ohio Pyle. Charles M. Boardman. Four collections. 

 Oct. 12, 1935, figured). Somerset Co.: Beck Spring. Mill Creek, Laurel Hill Mt. 

 C.M.B. July 26, 1947. Westmoreland Co.: On wet clay in roadside ditch, Laiael 

 Hill Mt., 9 mi. s.e. of Rector. H. N. Mozingo. Oct. 7, 1945. 



2. Atrichum undulatum [Linnaeus] Beauvois 



{Bryiim unditlatiim L. ) 

 Plate XXX 



Loosely cespitose, dull, dark green: stems erect, ranging from 1.5-6 cm 

 long, usually about 3-4 cm, mostly simple, more or less gray-radiculose below, 

 arising from a rhizone-like base; lower leaves minute, increasing in size up- 

 wards, the upper leaves lanceolate-lingulate, much crisped when dry, trans- 

 versely undulate when moist, sub-acute to obtuse, about 6 8 mm long, 1 mm 

 wide, serrulate to the middle or slightly below, the uppermost teeth double, 

 strong, being inserted in a border of 1-3 rows of brownish, pellucid to hyaline, 

 incrassate, narrow cells; the crests of the undulations on the back of the leaf 

 also often spinose in upper part of the leaf; leaf-cells elongate-rectangular at 

 base, reaching about .017 x .033 mm, becoming quadrate towards leaf-middle, 

 towards apex hexagonal and somewhat longer transversely and about .01 7-. 024 

 mm; costa strong, ending just below apex, sharply dorsally toothed, ventrally 

 with 3-6 longitudinal lamellae which each consist of 3-6 rows of cells similar 

 to those of the leaf-blade, the costa and its lamellae covering rarely m,ore than 

 one-fourth of the total leaf-width (in our region sometimes even narrower; 

 "1 11-1, 7 of median width" — Frye: seta erect, flexuose, somewhat sinistrorse, 

 smooth, lustrous castaneous, 2-5 cm long; capsule lustrous, becoming dull with 

 age, castaneous, cylindrical, arcuate to almost straight, inclined, smooth, about 

 4-5 x 1-1.3 mm; peristome single, the 32 teeth linear-lanceolate, obtuse, about 

 C.3 mm high, orange-pellucid along the median line, united in the lower third 

 into a reddish-orange basal membrane, the teeth covered (especially along the 

 margins) with a hyaline, densely but minutely papillose layer which, during 

 the winter, becomes deciduous, thus leaving the teeth perfectly smooth; spores 

 smooth, orange, spherical, about .016-.019 mm in diameter; mature in late 

 fall, operculum conic, curved linear- rostrate, about 2.5-3 mm long; calyptra 

 pale, roughened towards apex, covering about one-half to one-third of urn. 



Widely distributed throughout the North Temperate Zone on earth, par- 

 ticularly partly shaded clay banks; in North America extending as far :outh 

 as South Carolina and California. 



Common in our region — known from Allegheny, Beaver, Bedford, Butler, Clinton, 

 Crawford. Elk, Erie, Fayette, McKean, Somerset, Washington, and Westmoreland coun- 

 ties. Specimen figured: Hyner Creek, above Hyner. Clinton Co., July 15. 1908. O.E.J. 



