KEY. 171 



Corolla membranaceous, withering. Flowers whitish, small, 

 in a bracted spike, or head, on a naked scape. 



Plantago (878). 

 Herb with a stem, diffusely much branched, form- 

 ing patches. Stamens included. Corolla broadly bell- 

 shaped. Flowers small, white, sessile, cymose. Leaves 

 linear, subulate, opposite. 



Folypremum procumbens, L. 



353. (341.) I. Ovary 1, entire 356 



II. Ovary 1, deeply 4-lobed, with the style rising 

 from between the lobes, forming 4 achenia in fruit 377 



III. Ovaries 2 410 



356. Ovary 1-celled 357 



Ovary 2- to 6-celled 385 



357. Leaves submersed or floating. Aquatics 358 



Leaves not submersed 359 



358. Leaves round-heart-shaped, on very long petioles,, 

 which- bear an umbel of polygamous flowers, and often a 

 cluster of roots near the summit. Corolla wheel-shaped. 

 Two j)arietal placentae. 



Iiimnauthemum lacunosum, Griseb. 

 Leaves pectinately dissected into filiform segments, 

 scattered on the floating and rooting stems, and crowded at 

 the base of clustered peduncles, the latter much inflated be- 

 tween the joints. Calyx with linear lobes. Corolla salver- 

 shaped. Stamens included. A central placenta. 



Hottouia inflata, Ell. 



359. Stemless plants. Flowers on scapes. Leaves all 

 radical 3gO 



Plants with leafy stems 363 



3G0. Leaves trifoliolate, at the top of long petioles, 

 which are stipulate (membranaceous and sheathing) at the 

 base, springing from a thickish, creeping root-stock. Throat 

 and inner surface of the lobes of the short funnel-form 

 corolla white-bearded. Flowers racemed on the naked 

 scape. Menyanthes trifoliata, L. 

 Leaves simple and entire 361 



