98 American Midland Naturalist Monograph No. 6 



On moist rocks in woods, Japan and, in North America, from Nova 

 Scotia to Georgia and Minnesota, and in Mexico. Reported from Painesville, 

 Ohio (W. C. Werner) and in Pennsylvania. 



Fayette Co.: Meadow Run, Ohio F*yle. June 23. 1940. C. M. Boardman (figured). 

 Washington Co.: On sandstone rock on high hill, near Grier's Station. A. Linn and 

 J. S. Simonton. Oct. 5, 1898. 



4. Grimmia laevigata (Bridal) Bridel 



(G. campestjis Burch.; G. leucophaea Greville) 



Cespitose loosely in wide, dull gray-green tufts; hoary above: stems stout; 

 leaves close, larger towards top of stem, when dry imbricate-appressed, very 

 concave, oblong-oval to rather widely ovate, 1-1.5 mm long, plane-margined, 

 at the apex abruptly terminating in a hyaline, flanened, finely denticulated 

 hair; the smaller lower leaves acuminate but without the hair-point; costa nar- 

 row, ending in the apex; basal leaf -cells quadrate, except a few rectangular ones 

 near the costa, the upper smaller and rounded, all incrassate, non-sinuose, the 

 upper quite chlorophyllose: seta erect; capsule included, or emergent, 1-2 mm 

 long, elliptic, broadly oblong, brownish smooth when dry; annulus large; lid 

 conic-rostellate, short, peristome-teeth cleft to about the middle, cribrose below, 

 castaneous-pellucid; calyptra mitrate, lobed; spores mature in spring. 



On rocks, mainly non-calcareous, often granite or sandstone, almost cos- 

 mopolitan. In North America from New York and Pennsylvania to Alabama 

 and northwestward to Oklahoma; also in the west. Rare in our region. 



Blair Co.: Tyrone, T. P. James. (Poner's Catalogue). 



3. Rhacomitrium Bridel 



Dioicous: robust plants, loosely and widely cespitose, the mats green to 

 yellowish or blackish-green: stem without central strand, procumbent to erect, 

 radiculose at the base only, uniformly foliate, often with numerous short 

 branches giving the shoot a nodose appearance; leaves spreading to recurved- 

 spreading or sometimes secund, when dry appressed, from an ovate to oblong 

 base mostly lanceolate to lance-linear, more or less long-acuminate, often 

 piliferous, sometimes lingulate and obtuse, margins sometimes 2-layered and 

 sometimes recurved; costa mostly broad flat, and complete; cells nearly all with 

 sinuose or nodulose walls, often papillose, towards the base or sometimes all 

 over linear: seta long, straight, rarely curved, twisted; capsule erect, oblong to 

 cylindric, narrow-mouthed, smooth: annulus broad, curling off; teeth united 

 at the base but mostly cleft deeply into 2 (-3-4) filiform divisions, often very 

 long, trabeculate; spores small; operculum conic with a long subulate apex 

 from one-third to more than the length of the urn: calyptra mitrate, lobed, 

 not folded, subulate-rostrate, glabrous or rough. 



A world-wide genus ol: about 90 species, mostly on siliceous rocks: about 

 10 in North America; probably 2 species in our region. 



Key- to the Species 



A. Upper leaf-cells quadrate, lower ones linear; shoots not appearing nodose by arrangj- 



ment of short lateral branches B 



