POLYPODIACEAE. 467 



1. Pteris caudata L. Sp. PI. 1075. 1753. 



Pteridium caudatum Maxon, Proc. U. S. Nat. Mus. 23: 631. 1901. 



Pteris aquilina caudata Hook. Sp. Fil. 2: 196. 1858. 



Leaves erect, 1-2 m. tall; blades triangular in outline, 2-4-pinnate; 

 divisions pinnatifid, the ultimate segments narrow, with recurved margins, re- 

 mote from one another, scarcely deeurrent on the rachis except near the apex, 

 the larger with 1-12 similar but shorter segments. 



Pine-lands, scrub-lands and coppices, Abaco, Great Bahama, Andros, New Provi- 

 dence, Cat Island, Crooked Island, North Caicos : Florida; Bermuda; Jamaica; 

 Cuba: Hispaniola ; Porto Rico; Montserrat ; continental tropical America. SOUTH- 

 ERN BEACKEN. 



5. PYCNODOBIA Presl. Epim. 101. 1849. 



Mostly large ferns, the petioles not jointed with the rootstock, the leaves 

 variously divided. Sori marginal, continuous or nearly so, on a filiform or 

 narrow receptacle connecting the tips of the free veins; indusium simple, 

 membranous, formed by the reflexed margin of the leaf. Sporanges pedicelled, 

 provided with a vertical ring which bursts transversely. [Greek, thick-skinned.] 

 Many species, of warm and tropical regions. Type species: Pteris opaca 

 J. Smith. 



1. Pycnodoria longifolia (L.) Britton, FL Berm. 418. 1918. 



Pteris longifolia L. Sp. PI. 1074. 1753. 



Leaves somewhat spreading; petioles 1.5-3 dm. long, clothed below with 

 pale brown scales; blades simply pinnate, oblong-lanceolate, 3-6 dm. long; 

 pinnae linear, 4-8 mm. wide, entire, sessile; veins close, usually once branched; 

 indusium yellowish brown. 



In sink-holes. Great Bahama, Andros. New Providence : Florida : Bermuda ; 

 Jamaica ; Cuba ; Hispaniola ; Porto Rico ; St. Thomas ; St. Croix ; St. Kitts ; Guade- 

 loupe ; Dominica ; Martinique. 



In a monstrous form from Nicholl's Town, Andros, the pinnae are deeply cut 

 into linear lobes 4 cm. long or less. LONG-LEAVED BRAKE. 



6. ADIANTUM [Tourn,] L. Sp. PI. 3*794. 1753. 



Graceful ferns of rocky hillsides, woods, and ravines, with much divided 

 leaves and short marginal sori borne on the under side of the reflexed and 

 altered portion of the pinnule, which serves as an indusium. Stipes and 

 branches of the leaves slender or filiform, often polished and shining. [Name 

 ancient.] A genus of over 175 species, mostly of tropical America. Type 

 species: Adiantum Capillus-Veneris L. 



Leaf-segments stalked, cuneate at base. 1. A. tenerum. 



Leaf -segments sessile, truncate at base. 2. A. melanoleucum. 



1. Adiantum te"nerum Sw. Prodr. 135. 1788. 



Kootstock short, thick. Stipes smooth, nearly black, shining, 1-3 dm. long. 

 Blades 2 4-pinnate, 2-4 dm. long, glabrous; pinnules many, filiform-stalked, 

 subrhombic, membranous, cuneate at the base, dentate or incised above, deli- 

 cately many-veined, jointed with the stalk, 8^25 mm. long; sori few or several, 

 roundish or oblong. 



In caves, sink-holes and on steps, Abaco, Andros, New Providence, Eleuthera : 

 Florida ; Jamaica ; Cuba to St. Thomas and St. Croix ; St. Kitts to Tobago ; conti- 

 nental tropical America. The fern recorded by Coker as Adiantum Capillus-Veneris 

 L., is, apparently, this species. SLENDER MAIDEN-HAIR FERN. 



