270 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 11 



Leafy stems of small to medium size, complanate, ascending to erect from 

 a branched rhizome, forming dense greenish- to yellow-brown cushions or 

 scattered among other bryophytes; stems to 2 cm or more long, with leaves to 

 1.0 mm broad, branches frequent, both lateral and ventral, leafy. Rhizoids in 

 tufts from the scale-leaves of the rhizome. Leaves imbricate, short, broadly ovate, 

 acute or bifid by one or two cells, strongly concave, a ridge-keel and a pair of 

 wings, three to five cells wide developed in the upper half, the margins crenulate- 

 serrate or rarely dentate; leaf cells quadrate in outline, 12-16 p., mamillose projec- 

 tion developed on the ventral surface of most cells, the walls uniformly thickened, 

 the cuticle verruculose. Underleaves often large near the base of the stem, 

 orbicular-concave, soon becoming very small or reduced to a few cells throughout 

 most of the stem. Male and female inflorescences and sporophyte not seen. 

 PI. 62. Fig. 15, a-g. 



Habitat: On moist soil banks, moist sandstone bluffs and bases of trees, 

 forests. 



VENEZUELA: Estado Amazonas: Serrania Paru, Rio Venturi. Cumbre, 2000 m, 

 Cowan & Wurdack 31327 (type, NY). Estado Bolivar: Chimanta Massif, Torono-tepui, 

 2165-2180 m, Steyermark & Wurdack 695 p.p. (NY); se Cerro Venamo: escarpment, 1500 m, 

 Steyermark & Dunsterville 92586 p.p., 92595 p.p. (VEN) ; base of bluff, tributary of 

 Rio Venamo, 1220-1275 m, Steyermark & Dunsterville 92758 (VEN); Auyan-tepui: nr 

 Rio Churun. 1660 m, Steyermark 93823 (NY) ; n of El Liberator, 2050-2300 m, Steyermark 

 93946 p.p., 93947, 93948, 93950 p.p., 93951, 93952, 93955 (NY). 



16. Micropterygium steyermarkii Fulford, sp. now 



Caules foliosi ut videtur radiales, ad 10 mm longi, e viridibus ad luteo- 

 brunneos; folia lanceolata, acute carinata, ad basim alata, apice obtuso, margini- 

 bus crenulato-mamillosis, superficie crasse verruculosa; amphigastria similia sed 

 carinis absque carentia. Inflorescentiae femineae breves, basilares, bracteis 

 bracteolisque ex ovatis ad ovato-lanceolatas. Inflorescentia masculina et sporo- 

 phytum absentia. 



Leafy stems of small to medium size, appearing radial, green becoming 

 yellow-green, ascendent to erect from a branched rhizome, in tufts; stems to 

 10 mm long, with leaves, to 1 mm broad, the leaves and underleaves lanceolate, 

 stiff, widely spreading; leafy branches frequent, flagelliform branches occasional, 

 from the axils of the underleaves. Leaves widely spreading to patent, distant, 

 symmetric, long-lanceolate, 0.5-0.8 mm long, the tip blunt, sharp-keeled to the 

 base, the wing extending the whole length, three or four rows of cells wide, the 

 inner row elongate as in the keel, surface of the leaf and the keel coarsely 

 mamillose, the margins coarsely mamillose-crenulate from projecting cell thicken- 

 ings; cells of the lamina and outer part of the wing round-quadrate, 10-13 p., the 

 walls uniformly thickened, the trigones indistinct, cells along the keel two or 

 three times as long, each cell with a very large mamillose protuberance on the 

 outer surface, the cuticle, especially over the mamillae, coarsely verruculose. 

 Underleaves similar but without a keel and wing, the margins crenulate- 

 mamillose, the surface coarsely mamillose, the cells as in the leaf, i.e., of the 

 median portion elongate, of the lamina round-quadrate. Plants dioicous. Female 

 branches very short, from near the base of the leafy axis; the bracts and 

 bracteoles in three or four series, ovate to ovate-lanceolate, the innermost series 

 the largest, ending in several laciniae. Perianth, sporophytes and male inflores- 

 cence not seen. PI. 63. Fig. 16, a-h. 



Habitat: Base of a fern tree. 



