Crowfoot Family. 3 



similar, sessile; leaflets more or less 3-lobed, rounded to heart-shaped at 

 the base and long- petiolate. Flowers white or pinkish, umbellate. Sepals 

 5-10, large, broad ovate. Achenes terete, ribbed, sessile. 



A. thalictroides ( L. ) Spach. Rue Anemone. A low glabrous perennial 

 herb. 3-5 inches high with stem and radical leaves rising 1 from a cluster of tu- 

 berous roots. Upland woods; April-May; common. Occasionally double 

 flowered forms are found. ( S y tides moiitlia I ictro ides ( L. ) Hoffmg. ) 



TriALICTF^UM L. Meadow-Rue. Perennials, with alternate 2-3-ternately 

 compound leaves, the divisions and leaf ets stalked; and perfect, polygamous 

 or dioecious, paniculate or racemose flowers. Sepals 4-5, frequently petaloid. 

 Petals none. Stamens many, exserted. Fruit achenes. 



T. purpurascens L. Purple M. Stem 2-G feet high, frequently purplish; 

 leaves 3-4-ternate, the cauline nearly sessile; leaflets oblong-ovate to nearly 

 lanceolate, veiny, often waxy beneath, usually with three apical lobes; flow- 

 ers greenish or purplish, dioecious or polygamous; filaments narrow. Low 

 prairies and woods: May-June; common. 



T. polygamum MahL. Tall IT. Similar to the preceeding; plant not gland- 

 ular or waxy: filaments broadened. Reported as belonging to our flora. 



T. dioicum L. Early M. Stem 1-2 feet high, glabrous; leaves 3-4-ternate, 

 petioled; leaflets drooping, 3-9-lobed, rounded; flowers dioecious, purplish or 

 greenish. Rich upland woods and meadows; April-May; frequent; Winne- 

 shiek, Allamakee, Clayton, Fayette, Scott, Story, Cerro Gordo, Webster, Dall- 

 as, and Dickinson counties. 



RANUNCULUS L. Crowfoot. Buttercup. Annual or perennial herbs, 

 with alternate leaves, and white or yellow flowers. Flowers solitary, some- 

 times corymbed. Sepals 5, deciduous. Petals 5, rarely more or less, some- 

 times minute, with a nectariferous pit or scale at the base inside. Achenes 

 many, usually flattened, pointed, capitate or spicate. 



* Aquatics. 



R. trichophyllus Chaix. White Water C. Stem about 1 foot long; leaves 

 petioled. flacid, divided into capillary divisions, collapsing when withdrawn 

 from the water: petals ovate, twice as long as the calyx, white. Growing in 

 the soft mud in shallow water, immersed except the flower; June-August; in- 

 frequent; Winneshiek, Fayette, and Muscatine counties; reported from Ham- 

 ilton county. ( R. aquatilis var. trichophyllus of Gray's Manual. Batrachium 

 trichophyUum ( Chaix. ) Bossch. ) 



R. circinatus Sibth. Stiff Water C. Similar to the preceeding but leaves 

 sessile or nearly so, rigid, not collapsing; stipules conspicuous. In similar situ- 

 ations; June-August; infrequent; Fayette, Muscatine, Johnson, and Emmet 

 counties. ( B. divaricatum ( Schrank ) Wimm. ) 



R. multifidus Pursh. Yellow Water C. Stems floating or immersed, some- 

 times emersed; leaves repeatedly 3-forked, the ultimate divisions long, cap- 

 illary: out of water the leaves are often reniform, lobed or toothed or else the 

 divisions are shorter and linear; petals 5-8, bright yellow. In ponds and 

 slow streams: May-July: infrequent; Fayette, Scott, Muscatine, Johnson, 

 Story, Hardin, Emmett, Hamilton, Decatur, and Lyon counties. ( R. delphin- 

 if alius Torr. ) 



* * Terrestrial, but frequently growing in wet places; flowers yellow. 

 f Radical leaves deeply cleft or divided. 



R fascicularis Muhl. Plant pubescent, low; 3-10 inches high, fibrous roots 

 thickened: leaves 3-5-divided, divisions lobed and cleft, the ultimate segments 



