Jennings: Manual of Mosses— 31. Hypnaceae 221 



alar cells numerous and extending 1/2 the way up the margin of the body of 

 the leaf. — St. Louis, Mo., and Bushkill, eastern Penna. 



3. Amblystegium orthocladon (Beauvois) Jaeger 

 {Hypnum orthocladon Beauvois; A. varium var. orthocladon Husnot) 



Plates XLI, LXVI 



In deference to Dr. Grout's extensive work on this group of mosses I am 

 following him in placing this species under the genus Hygroamblystegiuni, 

 which see, page 233. 



4. Amblystegium juratzkanum Schimper 



Plate XLI 



Light yellowish-green, small: stems prostrate, rooting, slender, the branches 

 irregularly disposed, often ascending to erect, and rising to a height of 1-1.5 

 cm; leaves when dry usually squarrose-spreading and shriveled, ovate-lanceo- 

 late, gradually acuminate, about 1 to 1.4 mm long by 0.5 mm wide but quite 

 variable, almost entire to minutely denticulate, plane, the base narrowed, decu.-- 

 rent and slightly concave; costa yellowish, fairly strong, reaching to i.omswhit 

 above the middle; median leaf-cells prosenchymatous, linear-hexagonal, about 

 4-8:1, moderately incrassate, hyaline, the apical similar, the basal tending lo 

 sub-quadrate or shortly rectangular, the alar forming a rather distinct ^roup, 

 sub-pellucid, 2-3 times as wide as the median cells, decidedly incrassate, and 

 always as long or longer than wide; perichaetial leaves 1.5-2 mm long, acumi- 

 nate, thin, plicate: seta castaneous, smooth, about 2-2.5 cm high, when dry 

 flattened, flexuous, dextrorse; capsule unsymmetric, cernuous, decidedly arcu- 

 ate, 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 lypi- 

 cally hypnoid; teeth reddish, pellucid, strongly articulate and trabeculate, con- 

 fluent slightly at base, hyaline-margined, divisural zigzag, dorsal cross-striae 

 evident; segment 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 mem- 

 brane; spores rather clear, minutely papillose, medium to rather thin-walled, 

 mature in spring, .010-. 012 mm in diameter. 



On moist soil and stones; Europe, Asia, and, in North America, 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 Co.: 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 Co.: Linesville, 

 in Pymituning Swamp, June 11-12, 1907, and May 12, 1908. O.E.J, (figured). Erie 

 Co.: Presque Isle, June 9-11, 1905. O.E.J. Fayette Co.: Ohio Pyle, September 1-3, 

 1906. O.E.J. 



