6 GYMODOCEACBAE. 



Family 2. CYMODOCEACEAE Kerner. 



Manatbe-geass Family. 



Submerged marine perennial herbs, with long rootstoeks. Leaves linear, 

 sheathing. Flowers monoecious or dioecious, solitary or cymose. Staminate 

 flowers of 2 long-pedieelled anthers, the anthers 2-celled, longitudinally de- 

 hiscent. Pistillate flowers of 1 or 2 carpels, the 1 or 2 stigmas filiform. 

 Fruit nut-like, 1-seeded. Two known genera, the following. 



stigmas 2 ; leaves mostly terete. 1. Cymodocea. 



Stigma 1 ; leaves flat. 2. Halodule. 



1. CYMODOCEA Konig; Konig & Sims, Ann. Bot. 2: 96. 1805. 

 Leaves terete in our species, acute. Flowers dioecious. Pistillate flowers 

 of 2 carpels; stigmas 2. Seed pendulous. [Named for Cymodoce, one of the 

 Nereids.] Type species: Cymodocea aequorea Konig. 



1. CJymodocea manatorum Asehers. Sitzb. Ges. Naturf . Freunde, 1868 : 19. 1868. 



Rootstock branched, rooting at the nodes. Leaves 0.4-3.2 dm. long, terete 

 or nearly so, about 2 mm. thick, their bases enclosed by membranous stipular 

 sheaths 1-5 cm. long. 



Shallow salt water, Great Bahama, Abaco, Mariguana : — Bermuda ; Florida ; 

 West Indies. Manatee-geass. 



2. HALODULE End!. Gen.. 1368. 1841. 

 Marine perennials with jointed rootstoeks and linear, flat sheathing leaves, 

 the small flowers dioecious. Perianth wanting. Staminate flower of 2 anthers 

 unequally attached to a pedicel. Pistillate flower a solitary naked carpel; 

 style short; stigma one, slender. Fruit globular, small. [Greek, referring to 

 the saline habitat.] A few species of tropical and subtropical waters. Type 

 species: Diplanthera tridentata Steinh. 



1. Halodule Wrightii Asehers. Sitzb. Ges. Naturf. Preunde, 1868: 19. 1868. 



Diplanthera Wrightii Asehers. in E. & P. Nat. Pfl. Naohtr. 37. 1897. 



Eootstock slender, nearly white, 3 dm. long or longer, copiously rooting at 

 the nodes. Leaves narrowly linear, 1 mm. wide or less, acute, sheathing at the 

 base, the searious sheath 1-3 cm. long; anthers about 6 mm. long; fruit nearly 

 black. 



Shallow salt water, Rose Island, Bleuthera, Mariguana : — ^Florida ; Cuba ; Porto 

 Rico ; St. Thomas ; St. Croix ; Jamaica ; Martinique ; Panama. 



Order 3. ALISMALES. 



Aquatic or uliginous herbs, mostly aeaulescent and with rootstoeks. 

 Leaves alternate, mostly basal, broad or narrow. Flowers perfect, monoe- 

 cious or dioecious, clustered. Calyx of 3 sepals. Corolla of 3 thin petals, 

 or sometimes wanting. Stamens several or many; filaments slender or 

 short; anthers with inconspicuous connectives. Pistils few to many, dis- 

 tinct; ovary superior; style stout or slender; stigma small. Fruit a head 

 of achenes in the following family. 



