CERATOPHYLLACEAE (HORNWORT FAMILY) 95 



A Leaves peltate, on an elongated stem; flowers 1-2 cm. wide; carpels distinct; 



pistils 4-18, not dehiscent. W. E. Brasenia schreberi (WATER SHIELD) 



AA. Leaves not peltate, all basal; flowers 2.5-13.7 cm. wide; carpels united into a 



single dehiscent pistil. 



B. Sepals 4, flat; petals 2-3.5 cm. long, white or pinkish, epigynous. E. (Gk. 

 kastalia = a mythical fountain on Mt. Parnassus.) 



Castalia tetragona (SMALL WHITE WATER-LILY) 



BB. Sepals 8-12, concave; petals 1-1.5 cm - long, yellow, hypogynous. W. C. E. 

 Seeds edible. (White ones were dedicated by the Greeks to the water 

 nymphs.) Nymphaea polysepala (YELLOW POND-LILY) 



CERATOPHYLLACEAE (HORNWORT FAMILY) 



Herbs, perennial, aquatic, submerged; stems slender, branching. 

 Leaves whorled; threadlike or stag-horn-like, terminal tuft of leaves 

 slimy and persisting through the winter. Flowers extremely rare. 

 W. E. (Gk. keras = a horn, phyllon = a leaf; the leaves branch 

 Stag-horn-like.) Ceratophyllum demersum (HORNWORT) 



RANUNCULACEAE (BUTTERCUP FAMILY) 



Herbs or shrubs, annual or perennial, climbing when shrubby. 

 Leaves alternate or opposite (Clematis) or a single whorl (Anemone), 

 simple or compound; stipules none. Flowers regular or irregular. 

 Sepals 3-15, often petal-like, imbricated (except in Clematis). 

 Petals of about the same number as the sepals, rarely more, 

 rarely none. Stamens 10 to many, hypogynous. Carpels I to 

 many, often separate, in fruit becoming akenes or follicles or berries. 



A. Leaves either alternate or all basal. 

 B. Floweis spurless or i-spurred; leaves various. 

 C. Flowers regular; leaves various. 

 D. Leaves simple. 



E. Leaves entire; fruit of i-seeded akenes. MYOSURUS (p. 100) 



EE. Leaves either not entire, or else fruit of several-seeded follicles. 

 F. Petals none. 



G. Leaves entire or crenate; sepals 5-15; fruit of follicles; follicles several- 

 seeded, not 4-angled. CALTHA (p. 96) 

 GG. Leaves palmately lobed; sepals 4; fruit of akenes; akenes i -seeded, 

 4-angled. W. C. E. (Honor of E. R. von Trautvetter, a Russian bot- 

 anist.) Trautvetteria grandis (FALSE BUGBANE) 

 FF. Petals present. 



H. Plants glabrous; petals 15-25; fruit of many-seeded follicles. W. C. E. 

 (German trol = something round; referring to the form of the flower.) 

 Trollius laxus (SPREADING GLOBE-FLOWER) 

 HH. Plants either pubescent or petals fewer; fruit of i -seeded akenes. 



