264 American Midland Naturalist Monograph No. 6 



divisural distinct, cross-striolate below; the segments about as long, slightly 

 carinately split, the basal membrane reaching about two-fifths as high, the cilia 

 articulate and usually single; annulus compound, adherent; exothecial cells 

 yellowish-pellucid, laterally quite incrassate, oblong-quadrate to long-rectangu- 

 lar; spores yellowish, medium-walled, mmutely roughened, about .013-.015 

 mm, mature in late autumn or early winter. 



This is commonly sold in the Pittsburgh markets at Christmas time in 

 sheets and called "Log Moss." 



On earth, stones, roots, logs, etc., with us mainly on humus or rotten 

 wood, in moist woods; Europe, Asia, and from Canada southwards to Cali- 

 fornia and Georgia. 



Very common in our region. Now known in 15 counties in western Pennsylvania and 

 probably occurring in all. It is particularly abundant in the southwestern counties grow- 

 ing in sheets over decaying logs. Specimen figured: Wildwood Hollow, Allegheny Co., 

 Nov. 19. 1908. O.E.J. 



5. Stereodon cupressiformis [Lmnaeus] Lindberg 



{Hypnum cupressiforme Linnaeus; H. compressum Schuitz) 

 Widely cespitose in flat, soft tufts, usually yellowish or brownish-green: 

 stems up to 10 cm long, greenish, procumbent, irregularly pinnate, the branches 

 spreading or ascending, usually curved; leaves closely imbricate, concave at the 

 base, not decurrent, falcate-secund, lustrous, oblong- to ovate-lanceolate, nar- 

 rowed rather abruptly to a long acumination, plane-margined, typically entire, 

 sometimes denticulate towards the apex; costa none or very short and double; 

 median leaf-cells about 10:1, linear-vermicular, rather obtuse, the angular 

 sub-quadrate, numerous, rather opaque, a few at the extreme angles larger, 

 scarcely inflated, somewhat orange-pellucid, or hyaline, rather incrassate, the 

 auricles not well-defined; perichaetial leaves denticulate, not plicate: seta red, 

 about 3-4 cm long; capsule sub-erect, curved, sub-cylindric or oblong, castane- 

 ous, somewhat constricted below the mouth when drv; lid convex at base, with 

 an acuminate or sub-rostrate apex; peristome normally hypnoid; cilia usually 

 one or two; spores mature in late autumn or early winter. 



On soil, rocks, roots, and bases of trees, in moist woods or ravines; practi- 

 cally cosmopolitan, — in North America occurring from the Arctic regions to 

 the Gulf States. Rare in our region. Quite variable. There are a number of 

 named varieties. 



Cambria Co.: T. P. James. (Porter's Catalogue). McKean Co.: Three pockets 

 so-labeled in the Carnegie Muscim Herbarium are apparently typical S. fertilis and the 

 Porter Catalogue record is probably founded upon some of the same Burnett collections. 



5a. Stereodon cupressiformis var. filiformis (Bridel) Jennings 



(Hypnum cupressiforme var. filiforme Bridel) 

 Plate L 

 More slender, distantly pinnate, the branches long, very slender and almost 

 filiform; leaves very small, falcate-secund, more or less regularlv and neatly 

 imbricated in two rows. 



Habitat and range as for the species. 



