464 POLYPODIACEAE. 



toothed at the apex, falcately narrowed at the base, the margins thickened and 

 slightly revolute, the 40-50 nerves closely parallel; fruiting peduncle about 4 

 cm. long, 1.2 cm. thick below, 2 cm. thick at the top, densely pubescent; fruit- 

 ing cone oblong, puberulent, 7 cm. long, 4 cm. in diameter, its acute conic 

 tip 8 mm. high, its scales oblong, hexagonal, about 1.5 cm. wide and 8 mm. 

 high. 



Sandy coastal thicket, Clarence Town, Long Island. Endemic. Bahama Bay-rush. 



Phylum 2. PTERIDOPHYTA. 



Ferns and Fern-Allies. 



Plants containing woody and vascular tissues, producing spores 

 asexually, which, on germination, develop small flat mostly green 

 prothallia (gametophyte). On these are borne the reproductive 

 organs, the female known as archegones, the male as antherids. 

 From the fertilization of the egg in the archegone by spermato- 

 zoids produced in the antherid, the asexual phase (sporophyte) of 

 the plant is developed; this phase is represented by an ordinary 

 fern, lycopod, or horsetail. Comprising about 6000 living species, 

 of which more than three fourths are confined to tropical regions. 



Spores produced in sporanges borne on the leaves, or panicled or in special con- 

 ceptacles. 

 Spores all alike ; Bahama species all terrestrial or 



epiphytic plants. Order 1. Filicales. 



Spores of two sizes ; small floating plants. Order 2. Salviniales. 



Spores produced in sporanges borne in the axils of scale- 

 like leaves. Order 3. Lycopodiales. . 



Order 1. FILICALES. 



Spores all of one kind and size, produced in sporanges, which are borne 

 usually in clusters (sori) on the back of a leaf or on greatly modified 

 pinnae. 



Sporanges borne in sori on the back or the margin of a leaf, opening transversely. 



Fam. 1. POLYPODIACEAEu 



Sporanges in spikes or panicles, opening vertically. Fam. 2. Schizaeaceae. 



Family 1. POLYPODIACEAE R. Br. 



Fern Family. 



Ferns of various habit, the rootstocks horizontal and often elongated, 

 or short and erect, the leaves entire, pinnate, pinnatifid or decompound, 

 coiled in vernation, mostly with petioles (stipes). Sporanges borne in 

 clusters (sori) on the lower side or margins of the leaves or their segments, 

 stalked, provided with a vertical ring, opening transversely. Sori with or 

 without a membranous covering (indusium). Prothallium green. About 

 150 genera and 4,500 species of wide distribution. 



