82 KEY AND FLORA 



32. NYMPHJEACEiE. "Water Lily Family 



Perennial aquatic herbs. Leaves usually floating, often shield- 

 shaped. Flowers borne on naked scapes. Floral envelopes and 

 stamens all hypogynous or epigynous. Sepals 3-6. Petals 

 3-5 or often very numerous. Stamens many. Carpels 3 or 

 more, free or united. Pruit a berry or a group of separate 

 carpels. 



I. NYMPHiEA L. 



Eootstock horizontal, thick, cylindrical. Leaves heart-shaped, 

 floating or erect. Flowers yellow. Sepals 4-6, green on the 

 outside, obovate, concave. Petals many, hypogynous, the 

 inner ones becoming small and stamen-like. Stamens many, 

 hypogynous. Ovary cylindrical, many-celled; stigma disk- 

 shaped. Fruit ovoid.* 



1. N. advena Ait. Yellow Pond Lily, Cow Lily, Spatter- 

 DocK. Leaves oval or orbicular, rather thick, often downy beneath. 

 Flowers bright . yellow, 2-3 in. in diameter, depressed-globular. 

 Sepals 6. Petals thick and fleshy, truncate. Stamens in several 

 rows ; anthers nearly as long as the filaments. In slow streams and 

 still water.* 



II. CASTALIA Salisb. 



Rootstock horizontal, creeping extensively. Leaves float- 

 ing, entire, shield-shaped or heart-shaped. Flowers showy. 

 Sepals 4, greeii without, white within. Petals many, white, 

 becoming smaller towards the center. Stamens many, the 

 outer with broad and the inner with linear filaments. Ovary 

 many-celled, stigmas shield-shaped and radiating. Fruit berry- 

 like, many-seeded.* 



1. C. odorata Woodville and Wood. White Water Lily. Root- 

 stock large, branched but little. Leaves floating, entire, .the notch 

 narrow and basal lobes acute, green and smooth above, purple and 

 downy beneath. Petioles and peduncles slender. Flowers white, very- 

 fragrant, opening in the morning, 3-5 in. broad. Fruit globose ; seeds 

 inclosed in a membranaceous sac. In ponds and still water.* 



2. C. tuberosa Greene. Much like No. 1. Rootstock bearing loosely 

 attached, often compound tubers. Leaves round-kidney-shaped, sel- 

 dom purple beneath. Flowers larger than in No. 1, scentless or nearly 

 so. Slow streams, especially W. 



