SEMATOPHYLLACEAE. 499 



and clasping with smooth enlarged, yellow cells at angles; cells long and nar- 

 row with numerous small papillae; margins minutely and sharply toothed 

 nearly to the base; veins short or none. Autoicous; perichaetial leaves -nar- 

 rower and more acuminate, with smooth lax cells; pedicel up to 15 mm. long, 

 slender; capsule about 1.5 mm. long, horizontal, strongly contracted below the 

 mouth when dry; lid blunt; neck distinct; peristome pale yellow, its teeth stri- 

 ate at base, pale and papillose at apex, deeply lamellate at base within; keeled 

 segments slender, pointed; cilia 1 or 2, seldom perfect; spores small, smooth, 

 yellow, ripe in winter. 



On the ground in coppice, New Providence : Florida ; West Indies ; Mexico to 

 South America. FLAT TAXITHELIUM. 



Family 14. SEMATOPHYLLACEAE Brotherus. 

 SEMATOPHYLLUM FAMILY. 



Plants usually forming- dense tufts. Stems creeping; branches erect, 

 irregular and unequal, sometimes pinnate; leaves small, crowded, often 

 secund; veins short, double or lacking; cells usually much longer than wide, 

 smooth or papillose, those of the basal angles often larger, inflated or 

 square. Pedicel erect; capsule usually horizontal, without an annulus; 

 calyptra cucullate; lid usually with a long slender beak; peristome double. 

 Twelve genera and 448 species widely distributed in tropical regions. 



1. SEMATOPHYTrLUM Mitt. Journ. Linn. Soc. 8 : 5. 1864. 



Stems rarely pinnate with the branches usually short and crowded. Leaves 

 secund or spreading, faintly bicostate or ecostate, with the cells all smooth, the 

 alar cells enlarged, often vesicular; margins entire or minutely serrulate; 

 pedicels long or short; capsule with the lid long-beaked, often equaling the 

 urn; teeth deeply lamellate inside, sometimes with minute projections on the 

 outside, either with a zigzag median line or a deep central groove; endostome 

 with the keeled segments more or less perforate and the cilia one or two, usu- 

 ally shorter, often papillose. A large genus of 314 species, mostly from trop- 

 ical America. [Greek, in reference to the pointed leaves.] Type species: 

 Hypnum substrumulosum Hampe. 



Leaves recurved when dry ; perichaetial leaves longer, entire or subserrulate ; peri- 



stome-teeth not deeply grooved, with a zigzag median line. 



Leaf-cells rhomboid, 3-5 times longer than wide. 1. 8. subpinnatum. 



Leaf-cells linear, &-10 times longer than wide. 2. S.admistum. 



Leaves spreading when dry ; perichaetial leaves shorter and 



serrate ; peristome-teeth deeply grooved on the median line. 3. 8. sericifoliwm. 



1. Sematophyllum subpinnatum (Brid.) E. G. Britton, Bryol. 21: '28. 1918. 

 Leskea subpinnata Brid. Sp. Muse. 2: 54. 1812. 



Plants growing in bright or yellowish green cushions, usually on wood. 

 Stems creeping and rooting, irregularly pinnate, with ascending, more or less 

 circinate, simple branches; leaves crowded, recurved or secund when dry, 

 spreading when moist, with recurved tips and revolute margins, seldom reach- 

 ing 1 mm. in length by 0.4 mm. wide, concave, with flat or revolute, entire mar- 

 gins; apex acute or short-acuminate; veins short and double, obscure or none; 

 basal angles with 3-4 rows of square cells and a few larger inflated alar cells; 

 upper cells rhomboid, about 35 times longer than wide; perichaetial leaves 



