226 COMMON CANADIAN WILD PLANTS. 



3. S. gramin'ea, Michx. Scape very slender, erect. 

 Leaves varying from ovate-lanceolate to linear, scarcely ever 

 sagittate. ' 



4. S. ealyei'na, Engelm., var. spbhgiosa, Engelm. 

 Scape weak, and at length usually procumbent. Fertile 

 flowers perfect. Leaves broadly halberd-shai^ed with wide- 

 spreading lobes. Suhmerged leaves without blades. — Atl. 

 Prov. 



Order XCIX. HYDROCHARIDA'CE^. (Prog's-bit F.J 



Aquatic herbs, with dioecious or polygamo-dioecious flow- 

 ers on scape-like peduncles from a kind of spathe of one or 

 two leaves, the perianth in the fertile flowers of 6 pieces 

 united below into a tube which is adherent to the ovary. 

 Stigmas 3. Fruit ripening under water. 



Synopsis of the Gcucra. 



1. Klotle'a. Growing under water, the pistillate flowers alone coming 



to the surface. Stem leafy and hraneWng. Perianth of the fertile 

 flowers witha 6-lobed spreading limb, the tube prolonged to an 

 extraordinary length, thread-like. Leaves crowded, pellucid, 1- 

 nerved, sessile, whorled In threes or fours. Stamens 3-9. 



2. Viillisue'rla. Nothing but the pistillate flowers above the surface, 



these on scapes of great length, and after fertilizatiou drawn 

 below the surface by the spiral coiling of the scapes. Tube of 

 the perianth not prolonged. Leaves linear, thin, long and ribbon- 

 like. 

 (In bpth genera the staminate flowers break gff spontaneously and 

 float on*the surface around the pistillate ones, shedding their pollen 

 upon therh.) 



ELODE'A, Michx. Water-weed. 



E. Canadensis, Michx. {Anach'aris Canadensis, Plan- 

 chon.) — Common in slow waters. 



a. VJlLLISNE'UIA, L. Tape-Geass. Eel-gkass. 

 V. spira'lis, I. Leaves 1-2 feet long. — Common in slow 

 waters. 



Order C. ORCHIDA'CEiE. (Orchis Family.) 



Herbs, well marked by the peculiar arrangement of the 

 stamens, these beiiig gynandrous, that isj bofno on or adher- 



