652 ORCHIDACE^E. 



ORDER NAIADACE^E. 



NAIAS, L. 



N. major, All. Stem muricate ; leaves broadly linear, serrate-dentate, 

 with muricaie teetli, the sheaths entire ; flowers dioecious ; anthers 4-valvecl ; 

 style very short; stigmas 3; achenium elliptical, obscurely reticulate. 

 South Florida. 



HALOPHILA, Thouars. 



Flowers dioecious, axillary, solitary. Perianth 2-leaved. Stamens 3, mon- 

 adelphous ; anthers 1-celled. Ovary 1-celled, with numerous parietal ovules. 

 Style long, filiform ; stigmas 3-5, penicillate. Capsule indehiscent. Seeds 

 globular. Embryo in copious albumen. Marine herbs, with creeping stems, 

 and opposite pellucid stipulate leaves. 



H. Engelmannii, Ascherson. Stem filiform, much branched ; leaves, 

 seemingly whorled at the end of the branches, linear-oblong, 3-nerved, 

 sharply serrulate (!' or less long); flowers and fruit unknown. Muddy 

 coves along the west coast of Florida. 



POTAMOGETON, Tourr. 



P. amplifolius, Tuck. Stem simple ; leaves large, oblong or oval- 

 lanceolate, acutish, long-petioled ; the submerged ones lanceolate, undulate; 

 stipules very long, pointed ; peduncles stout, fruit obliquely obovate, bluntly 

 keeled. Ponds on the mountains of Georgia, and northward. 



P. pulcher, Tuck. Closely resembles the preceding, but the stipules 

 short and obtuse, and the fruit sharply 3 keeled on the back when dry. 

 Georgia (Leconte). 



ORDER ORCHIDACE^E. 

 EPIDENDRUM, L. 



E. COChleatum, L. Stem tuber-like, ovate-lanceolate, 2-edged, scaly, 

 2-leaved ; leaves oblong-lanceolate, acute, as long as the few-flowered scape ; 

 flowers racemose, short-bracted ; sepals and petals greenish, broadly linear, 

 recurved ; lip much shorter, purple, entire, cordate-roundish, cochleate, acute, 

 2-callous at the base. South Florida ( Garber). Stem 1 high. Leaves 1' 

 wide. Flowers 1' - !' long. 



E. umbellatum, Swartz. Stem leafy; leaves oblong, obtuse (2' -3' 

 long) ; flowers umbellate, greenish ; bracts ovate ; sepals oblong ; petals lin- 

 ear ; lip reniform-roundish, obscurely 3-lobed, veiny, 2-callous at the base ; 

 column denticulate. Miami, South Florida (Garber). Stem & -12' high. 

 Flowers 6" -8" long. 



E. nocturnum, L. Stem leafy ; leaves oblong or oval, obtuse ; flowers 

 1-2, terminal, white or yellowish, long-peduncled ; petals large, linear, acu- 



