POLYPODIACEAE 



17 



the hammock floor, on logs, stumps, and on tree-trunks, 

 and high up on the branches. This fern is not as com- 

 mon on the Florida Keys as on the Everglade Keys, 

 although it grows sparingly on most of the larger 

 islands of the Florida reef. It is widely distributed in 

 tropical America, and was discovered in Florida in the 

 earlier half of the last century. In Florida its range 

 extends about half way up the peninsula. 



5. VITTABIA J. E. Smith 



Slender, tufted, epiphytic plants. Leaves grass-like, 

 crowded on the short rootstock, pendent ; blades nar- 

 rowly linear and elongate, entire, often strongly revo- 

 !ute. Veins obscure, forming a single row of areolae 

 on each side of the midrib. Sori 

 linear, continuous in a single margi- 

 nal or intramarginal groove, some- 

 times partly covered with the slightly 

 produced and revolute margin of 

 the leaf-blade. Indusia wanting. 

 About fifty species, natives of the 

 tropics. 



1. V. lineata (L.) J. E. Smith. 

 Eootstockwith short clustered branches, 

 densely scaly: leaves many together, 

 sometimes exceedingly numerous, 

 densely clustered, drooping or pen- 

 dent, 1-12 dm. long; blades narrowly 

 elongate-linear, usually between 2 

 mm. and 3 mm. wide, smooth and 

 shining: veins very obscure: sori 

 borne in an intramarginal continu- 

 ous groove. (GRASS-FERN. SHOE- 

 STRING-FERN. BEARD-FERN.) Ham- 



