4 ALSINACEAE. 



1. C. manatorum Aschers. Plants growing on sandy bottoms, the short stems 

 arising at the nodes: leaf -blades narrowly linear, 5-25 cm. long: fruits 6-7 mm. 

 long, short-stipitate, prominently beaked. Shallow water, U. S. keys, U. keys, 

 and L. keys. [E. K.]. (Ber., Bah., Cuba, Ant.) MANATEE-GRASS. 



2. HALODULE Endl. Eootstocks elongate. Leaves flat above the 

 sheaths. Flowers borne in the leaf-sheaths, or the staminate long-exserted. 



1. H. Wrightii Aschers. Plants growing on sandy bottoms, the short stems 

 arising from the nodes of the rootstock: leaf -blades narrowly linear, 3-40 cm. 

 long: nutlets sessile. Shallow water. (Cuba, Ant.) 



Order ALISMALES. 



Marsh or aquatic herbs. Leaves alternate, mere phyllodia, or with 

 dilated blades. Flowers regular. Perianth of sepals and usually also of 

 petals. Androecium of 3-6 stamens or more. Gynoecium of 3-many 

 carpels. 



FAMILY 1. ALISMACEAE. WATER-PLANTAIN FAMILY. 



Annual or perennial herbs. Leaves basal, the blades flat, often with 

 basal lobes, or mere phyllodia. Flowers perfect, monoecious or dioecious, 

 whorled. Sepals herbaceous. Petals tender, white or pink. Gynoecium of 

 few to many carpels. Fruit a head of flattened or turgid achenes. 



Flowers perfect : carpel-bodies turgid. 1. ECHINODORCS. 



Flowers monoecious or dioecious : carpel-bodies flat, sometimes 



ridged or winged. 2. SAGITTABIA. 



1. ECHINODORUS L. C. Eich. Leaves with rounded basal lobes. Flowers 

 perfect, in racemes or panicles. Stamens 12-30. Achenes numerous, with turgid 

 bodies, in a bristly naked head. 



1. E. cordifolius (L.) Griseb. Leaf -blades lanceolate to broadly ovate, 4-20 

 cm. long: scapes 1-5 dm. tall, the flower whorls somewhat remote: petals 4-6 

 mm. long: fruit heads 4-6 mm. thick: achenes 2.5-3 mm. long, long-beaked. 

 Pools and lime-sinks, L. keys. (Bah., Cuba, Ant.) BUR-HEAD. 



2. SAGITTAEIA L. Leaves often with basal lobes, sometimes lobeless or 

 mere phyllodia. Flowers monoecious or dioecious, the upper ones usually stami- 

 nate. Stamens mainly numerous. Achenes numerous, with flat bodies, in dense 

 heads. 



1. S. lancifolia L. Leaf -blades elliptic or nearly so to narrowly elliptic-lanceo- 

 late, 30-60 cm. long, mainly 5-9-nerved: pedicels of pistillate flower? relatively 

 long, their bracts of a lanceolate type: achenes 2.5-3 mm. long. Lime-sinks 

 and pools, L. keys. [E. K.] (Bah., Cuba, Ant.) ARROW-HEAD. 



Order HYDROCHAEITALES. 



Perennial aquatic herbs with rootstocks. Leaves usually with blades. 

 Flowers monoecious or dioecious, or rarely perfect, from spathes. Perianth 

 double, or corolla wanting. Androecium of 1-12 stamens. Gynoecium 

 3-15-carpellary. Ovary inferior. Fruit capsular or baccate. 



Gynoecium 3-carpellary, or rarely 2-, 4- or 5-carpellary : ovary 1-celled : stigmas 3. 



Fam. 1. ELODEACEAE. 

 Gynoecium 6-12-carpellary : ovary 6-12-celled : stigmas 



6-12. Fam. 2. HYDROCHAHITACEAE. 



