242 DIOECIA, DECANDRIl. 



tago. Are the stamina also really monadelphous? and 8 to 

 12? " alternated upon an axis forked at its summii!" Osg. 

 Seeds hirsute; capsules globose and recurved. Radicles 

 pubescent, 



800. * UDORA. Elodea. Michaux, 



Spathe bifid. — Masc. Cflii^ 3 -parted. CoroU 

 la of 3 petals. Stamina 9, 3 of them interior. 

 Fem. Calix 3-partcd, tube very long. Petals 

 3. Sterile filaments 3. Utriculus about 3-seed- 

 ed. Seeds cylindric. 



A submersed aquatic; roots fixed; Ftem diffusel}- dicho- 

 tomous; leaves entire, verticillated in 3s and 4s; flowers 

 axillary, very small and evanescent, the female emerg- 

 ing-; the male migratory, breaking off connection usually 

 with the parent plant, it instantly expands to tlie light, 

 the anthers also burst with elasticity and the granular 

 pollen vaguely floats upon the surface of the water 

 Grains of pollen didymous, or 4-lobed, lobes nearly sphe- 

 rical. Gemraule of the seed inverted. 



If. canadejisis. Leaves verticillate in 3s and 4s; oblong- 

 linear, minutely subserrulate, partly obtuse. 



EloJe a canadensis. Mich. Serpic2dax}erticillata.'S\\x\\\. 

 Catal. p. 84. S. ordj£'?2?a//*. Ph. 1. p. 33. Hab. In still 

 waters, from Canada to Virginia. The plant without 

 flowers resembles an aquatic moss (such as Tctraphis pel- 

 hicida.) Utriculus 1-celled, conic. Tube of the calix 

 filiform, 4 to 12 inches long. For a figure of the seed of 

 this genus, which appears to hold an intermediate station 

 betwixt Vidlisveria and Hydrocharis, see Annales du Mu- 

 seum, 17. p. 232. t. 1. f 30. Flowers scarcely larger than 

 those of a Jungermannia; petals of the male flower ligu- 

 late-spathulate; stigmas of the female 3, ligulate, reflected 

 and bifid, partly crested. 



Serpicula verticillata of Roxburg, is probably a se- 

 cond species of this very distinct genus. 



Order X.— DECANDRIA. 



^01. CARICA. L. (Papaw Tree.) 



Masc. Calix scarcely any. Corolla o-cleft. 

 funnelform. Filaments in the tube of the corol- 



