Order 136.— GREENBRIERS. 305 



Analysis of the Genera. 



1 Frog"s-Ut. Loaves all radical, round-cordate, sponf^y beneath, floating in stasrnant 

 waters. Flowers dicecious, white, the fertile on short, the sterile on long (3') 

 peduncles. Berry many-?eeded. Limno'bium. 



i Ditch-moss. Leaves crowded on the long ?xibmersed stems opposite or whorled, linear- 

 oblong. Perianth Avhite, 6-parted, its base extended into a capillary tube 4-10' 

 long ! Stigmas 3. la brooks and rivers. Anach'aris. 



3 Eel-grass. Leaves all radical, grass-like in water. Flowers dioecious, the fertile white, 

 one on each long spiral thread-form scape ; the sterile in clusters at the root, but 

 breaking away and arising to the surface to open and shed their pollen. 



Vallisne'ria spiralis. 



Okder OXXXV. PONTEDERIACEiE. Pontederiads. 



Aquatic herbs with more or less irregular perfect flowers, with the 

 perianth colored, tubular, 6-parted, stamens 3 or 6, and style 1 ; 

 ovavy free ; capsule 3 or 1-celled, co or 1-seeded. 



Analysis of the Genera. 



* StaiMf lis 6, unequal. Perianth blue, 2-lipped. Utricle 1-seeded. Pontederia. 1 



* Stamens 3, unequal, the lower one sagittate. Capsule 3-celled, CO-seeded. Perianth 



white or blue, 6-parted, with a slender tube. Heteranthe'ra. 



* Stamens 3, equal. Capsule 1-celled, CO-seedod. Perianth regularly C-parted, yellow, its 



tube very long (2-3') and slender. Leaves grass-like, growing wholly under water. 

 Water Star-grass. Schol'lera. 



1. PONTEDE'RIA. Pickerel-weed. 



Large showy lierbs growing in patches extending from the shore to 

 deep water. Leaves radical, long-stalked. Stem or scape bearing 1 leaf 

 and a terminal spike of showy flowers lasting but a day. 



1 P. cordifo'lia. Leaves between heart-and arrow-shaped, blunt, very smooth, and shin- 



ing. Scape stout, arising l-2f. above the water. Flowers violet blue, very irregular, 

 in a spike 2 or 3' long. After flowering the corolla rolls downward from the top, 

 persisting and withering on the 1-sceded fruit. Common. July. 



2 P. lancifo'lia. Leaves lance-oblong to lance-linear, rather acute at each end. South. 



Order CXXXVI. SMILACACE.E. Greenbriers. 



Herbs or shrubs often climbing. Leaves reticulate-veined. Fl^. dicecious ; 

 Tperianth 6-parted, regular, free from the 3-cclled ovary. Fruit a berry. 



1. SMILxVX. Greenbrier. 

 Leaves palmate-veined, entire, petiolate, with a pair of tendrils in tb«^ 

 place of stipules. (See Fig. 95.) Flowers greenish, in axillary umbels 



