60 A MANUAL OF MOSSES 



7. DICRANELLA Schimper. 



Dioicous, rarely pseudautoicous : mainly small, gregarious, 

 or cespitose, terrestrial : stem erect, thickly foliate, sparsely 

 radiculose ; leaves somewhat lustrous, from a sheathing base 

 abruptly subulate and squarrose-spreading, or from a non- 

 sheathing' base gradually linear to subulate and stiffly erect to 



O O J ^ 



falcate-secund, mostly with plane edges ; costa strong, mostly 

 percurrent, often filling the acumen ; leaf-cells elongate-rectan- 

 gular to linear: seta erect; capsule cernuous, unsymmetric. 

 short, short-necked, often strumate, or erect and symmetric; 

 peristome-teeth usually present, mostly unequally subulately 

 2-3-cleft, papillose above, at the extreme base united to form 

 more or less of a basal membrane, exteriorly finely vertically 

 striate ; operculum conic-rostrate or obliquely long-rostrate, 

 sometimes as long or even longer than the urn. 



A large and cosmopolitan genus of about 130 species ; about 

 32 species in North America ; at least 4 species in our region. 



Key to the Species. 



a. Costa wide and flat and not well-defined at base; peristome weak- 

 ly papillose; annulus often differentiated. b. 



a. Costa narrow and sharply defined at base: peristome densely 

 papillose; annulus not differentiated. e. 



b. Seta red. c. 



b. Seta yellowish. d. 



c. Leaves squarrose from a sheathing base. (D. crisp a [Ehfhart] 



Schimper). 



c. Leaves not squarrose nor from a sheathing base. 



(D. curvata [Hedwig] 



Schimper). 



d. Capsules erect and symmetric. i. D. fitzgeraldi. 



d. Capsules more or less cernuous. 2. D. heteromalla. 



e Leaves entire. 4. D. i>aria. 



e. Leaves serrulate or denticulate. 3. D. rufcscciis. 



1. Dicranella fitzgeraldi Renauld and Cardot. 

 (D. heteromalla var. fitsgeraldi Grout). 



(Plate VI) 



Rather densely cespitose, yellowish-green : stem 5-10 mm. 

 long, mostly simple, erect, leaves crowded, erect-spreading, 

 sometimes subsecund, about 3-3.5 mm. long, up to 0.5 mm. 

 broad at base, from the lance-ovate base narrowing above 

 into a long, canaliculate-subulate, denticulate apex ; costa at 

 base rather indistinct, about one-fourth to one-third the width 

 of the leaf, strong above and constituting most of the acumina- 

 tion ; basal leaf-cells elongate-rectangular or sub-rectangular, 

 reaching 8x55 microns, hyaline, a few in the extreme alar por- 

 tion often quadrate, median cells quadrate : seta erect, yellowish- 

 red, becoming quite dark brownish-red when old, about 7-8 

 mm. long, when dry sinistrorse in the lower half and dextrorse 



