Ranunculaceae 151 



form. Fruit an indehiscent nut or achene. Endosperm 

 none ; cotyledons 4, verticillate. 



1. CERATOPHYLLUM L. HORNWORT. 



Leaves crowded in verticils, linear or filiform, spinu- 

 lose-serrulate, forked. Staminate and pistillate flowers, 

 generally at different nodes. Stamens 10-20 ; anthers 

 about equaling the perianth. Ovary and fruit slightly 

 exceeding the sepals, the fruit beaked with the long per- 

 sistent style. 



1. C. demersum L. Stems 2-9 dm. long, leaves 2-3-times 

 forked, the end of the segments capillary and rigid, 8-25 mm. 

 long, fruit oval, 4-6 mm. long, smooth or tuberculate, sometimes 

 winged or with 2 basal spurs on each side. 



In ponds and slow streams, frequent throughout our range. May-July. 



Family 31. RANUNCULACEAE. CROWFOOT 

 FAMILY. 



Annual or perennial herbs or rarely climbing shrubs, 

 with alternate or opposite, simple or compound, exstip- 

 ulate leaves. Flowers regular or irregular. Sepals 

 3-15, generally caducous, often petal-like. Petals usu- 

 ally of the same number, sometimes wanting. Stamens 

 many, hypogynous, longitudinally dehiscent. Carpels 

 many or rarely solitary, 1-celled, 1-many-ovuled. 

 Ovules anatropous. Fruit achenes, follicles or berries. 

 Endosperm present. 



Flowers perfect. 

 Fruit a follicle. 



Sepals herbaceous, persistent. 1. PAEONIA. 



Sepals petal-like, deciduous. 



Petals all spurred. 2. AQUILEGIA. 



Upper sepal spurred. 3. DELPHINIUM. 



Fruit an achene. 



Woody climbers ; petals wanting. 4. CLEMATIS. 



Herbs. 



Achene longitudinally nerved. 5. OXYGBAPHIS. 



Achene not longitudinally nerved. 6. RANUNCULUS. 



Flowers dioecious, greenish; petals none. 7. THALICTRUM. 



