stylopodium conic; fruit 3-6 mm. long, nearly orbicular, glabrate but hispidulous 

 when young, dorsal ribs narrowly winged, lateral ribs more broadly winged, these 

 nearly as wide as the body; oil tubes solitary in the intervals, sometimes in pairs, 

 2 to 4 on the commissure; seed face slightly concave, the seed remaining attached 

 to the pericarp. 



In wet meadows, bogs and in wet mud in partial shade along streams in N. M. 

 (Taos, Rio Arriba and San Juan cos.) and Ariz. (Apache and Coconino cos.), 

 July-Aug.; n.w, Wyo., s. Mont., Ida., s. to n. N.M. and n. Ariz. 



25. Oxypolis Raf. Hog-fennel 



Plants slender, erect, caulescent, glabrous, herbaceous, perennial from fascicled 

 tubers; leaves simply pinnate to ternate or reduced to hollow acute septate phyl- 

 lodes; leaflets (when present) broad or narrow, serrate to incised, mostly distinct 

 and sessile: inflorescence of compound umbels, the peduncles terminal and axillary; 

 involucre of a few slender bracts or lacking; involucel similar to the involucre or 

 lacking; rays few to numerous, usually spreading-ascending, the slender pedicels 

 ascending to spreading; flowers white or purple, the calyx teeth prominent or 

 minute, the stylopodium conic; carpophore divided to the base; fruit oblong to 

 obovoid, strongly flattened dorsally, glabrous, the dorsal ribs filiform, the lateral 

 broadly thin-winged and nerved dorsally at the inner margin to give the appearance 

 of 5 filiform dorsal ribs; oil tubes large, solitary in the intervals, 2 to 6 on the 

 commissure, the seed face plane; strengthening cells beneath the dorsal ribs and the 

 nerves of the lateral wings. 



A genus of about half a dozen species, chiefly of the eastern and southeastern 

 United States. 



1. Leaves reduced to cylindrical or flattened entire septate phyllodes 



1. O. filiformus. 



1. Leaves pinnate; leaflets mostly toothed (2) 



2(1). Leaflets entire or sharply-toothed; lateral wings broad; rays 15 to 45 



2. O. rigidior. 



2. Leaflets serrate to crenate-toothed; lateral wings narrow; rays 5 to 12 



3. O. Fendleri. 



1. Oxypolis filiformis (Walt.) Britt. Fig. 595. 



Plant to 14 dm. high; leaves reduced to hollow septate phyllodes 2-6 dm. long; 

 peduncles 2-9 cm. long; involucre of several linear to lanceolate bracts 5-15 mm. 

 long; involucel of linear to lanceolate bractlets 2-4 mm. long; rays 8 to 14, spread- 

 ing, slightly unequal, 2-4.5 cm. long; pedicels spreading, 5-10 mm. long; calyx 

 teeth conspicuous; fruit oval or obovoid, 5-8 mm. long, 3-5 mm. broad, the lateral 

 wings thinner than the body. 



Wet places in the Timber Belt and the Blackland and Coastal prairies, July-Sept.; 

 from Va. s. to Fla. and w. to Tex.; also Bah. I. and Cuba. 



2. Oxypolis rigidior (L.) Raf. Cowbane, water-dropwort. Fig. 596. 



Plant 6-15 dm. high; leaves oval to triangular or lanceolate, to 30 cm. long and 

 25 cm. wide, pinnate; leaflets 5 to 9, lanceolate or linear, i^motely salient-dentate 

 or entire; peduncles 6-30 cm. long; involucre of a few linear bracts 1-2 cm. long; 

 involucel of a few linear bractlets 3-5 mm. long; rays 15 to 45, spreading, subequal, 

 3-12 cm. long; pedicels spreading, 5-15 mm. long; calyx teeth conspicuous; fruit 

 oval or oblong, 4-7 mm. long, 2.5-4 mm. broad. 



Along streams and in other wet places in Okla. {Waterfall) and in Tex. in the 

 Timber Belt and the Blackland and Coastal prairies, Aug.-Oct.; from N.Y., s. to 

 S.C, w. to Minn, and Tex. 



1251 



