KEY. 157 



363. Leaves 2-ranked, equitant, linear. Calyx of 3 

 bracts. Corolla (perianth), of 6 petals (sepals). Ovaries 3, 

 united at the base. Stamens 6. Stem scape-like, leafy only 

 at the base, bearing a close raceme of white or greenish 

 flowei-s. Tofielda (735). 



Leaves not 2-ranked, nor equitant . . . . j 264 



364. Leaves centrally peltate, elliptical, entire, 2-3 inches 

 in width, floating. Flowers axillary, small, dark purple, 

 rising to the surface of the water on slender axillary pedun- 

 cles. Stalks clothed with clear jelly. Stamens 12-24. 

 Pistils 4-18. Brasenia peltata, Pursh. 



Leaves not peltate 265 



365. Pistils indefinite, in a dense whorl or head, or in a 

 long slender spike. Acaulescent herbs 266 



Pistils definite 268 



366. Pistils spiked on a slender receptacle, usually 1 inch 

 long. Seed suspended. Leaves (radical) linear. Scapes 1- 

 flowered. Petals long-clawed. Stamens 5-20. Sepals and 

 petals 5. Myosurus minimus, L. 



Pistils in a roundish, or triangular whorl or head. 

 Sepals and petals 3. Leaves petioled, 5-7-nerved 267 



367. Stamens 6. Achenia not beaked. 



Alisma Flantago, L.' 

 Stamens 9-20. Achenia beaked. Uchinodorus. 



368. Calyx of 3-5 sepals 270 



Calyx S-, or (apparently) 10-cleft 269 



369. Calyx 5-cleft. Follicles 3-12. Shrubs or herbs 



58 

 Calyx apparentljr 10-, really 6-cleft, with 5 bractlets. 

 Petals 5, linear-oblong, minute, yellow, inserted with the 5 

 stamens into the margin of a woolly disk. Achenia 5-10. 

 Styles lateral. Leaves 3-foliolate ; leaflets wedge-shaped, 3- 

 toothed. Sibbaldia procumbens, L. 

 870. Leaves simple. Herbs succulent, and usually 

 fleshy 271 



Leaves pinnate, with 5, incisely lobed and toothed 

 leaflets. Sepals and petals 5, the latter smaller, clawed, 

 slightly _ 2-lobed. Stamens and pistils 5-15. A shrubby 

 plant, with polygamous, dull purple flowers, in compound, 

 drooping racemes. Xauthorrhiza apiifolia, L'Her. (650). 



