302 UMBELLIFERAE (PARSNIP FAMILY) 



24. OXYPOLIS Raf. 



Smooth, erect, swamp herbs, with fascicled tubers, leaves simply pinnate or 

 ternate or reduced to petioles, involucre of few bracts or none, involucels of 

 numerous small bractlets or none, and white flowers. Calyx-teeth evident. 

 Fruit flattened laterally, ovate to obovate, glabrous. Carpel with dorsal and 

 intermediate ribs filiform; lateral wings closely contiguous to those of the 

 other carpel and nerved dorsally at the inner margin (giving the appearance 

 of 5 filiform ribs on the* back of each carpel); strengthening cells beneath the 

 dorsal ribs and nerves of the lateral wings; stylopodium thick, short-conical; 

 oil-tubes solitary in the intervals, 2-6 on the commissural side. Seed face 

 plane. Archemora. 



1. Oxy polls Fendleri (Gray) Heller, Bull. Torr. Bot. Club 24: 478. 1897. 

 Stem slender, simple, 3-6 dm. high, from a large fascicle of tubers (2.5 cm. 

 long): leaves pinnate, 5-9-f oliolate ; leaflets ovate or oblong (or lanceolate in 

 upper leaves), obtuse, 2.5-5 cm. long, incisely serrate: umbel unequally 

 5-12-rayed, with neither involuore nor involucels; rays 1-3.5 cm. long; ped- 

 icels 4-8 mm. long: fruit ovate, scarcely 4 mm. long, with rather prominent 

 dorsal and intermediate ribs and narrower lateral wings; oil-tubes 2-4 on the 

 commissural side. In the mountains of our range. 



25. LEPTOTAENIA Nutt. 



Usually tall and stout, glabrous, nearly acaulescent perennials, with thick 

 often very large fusiform roots, usually large pinnately decompound leaves, 

 involucre of few bracts or none, involucels of numerous small bractlets, and 

 yellow or purple flowers. Calyx-teeth obsolete or sometimes evident. Fruit 

 flattened dorsally, oblong-elliptical, glabrous. Carpel with dorsal and inter- 

 mediate ribs, filiform or obscure; lateral wings very thick and corky, with 

 large groups of thick-walled strengthening cells; commissural face with a 

 prominent central longitudinal ridge left after separation from the carpo- 

 phore; stylopodium wanting; oil-tubes 3-6 in the intervals, 4-6 on the com- 

 missural side, mostly small, sometimes obsolete. Seed very flat, with plane 

 or slightly concave face. 



Leaves finely dissected; oil-tubes mostly wanting 1. L. multifida. 



Leaves less dissected; oil-tubes present . . . . . . . 2. L. Eatonii. 



1. Leptotaenia multifida Nutt. T. & G. Fl. 1: 630. 1840. Leaves finely 

 dissected: umbels mostly without involucre; pedicels of the fruit 6-24 mm. 

 long; flowers purple or yellow: fruit 8-12 mm. long, and with no strengthening 

 cells in the almost obsolete dorsal and intermediate ribs: seed face concave, 

 the carpel section being crescentic.. Montana to New Mexico. 



2. Leptotaenia Eatonii C. & Rf Rev. N. Am. Umbell. 52. 1888. Like L. 

 multifida, but with less dissected leaves: umbels few-rayed; pedicels of fruit 

 8-12 mm. long: fruit 16-18 mm. long, 8-10 mm. broad, flatter and thinner 

 than in any other species; oil-tubes 4-6 in the intervals, 4 on the commissural 

 side, a prominent corky nerve on the commissural face of the lateral wing 

 near the inner margin: seed face plane. Western Wyoming, Utah, and Idaho. 



26. COGSWELLIA Raf. 



Acaulescent or short caulescent, dry ground perennials, with fusiform or 

 tuberous roots, ternate (sometimes pinnate) to dissected leaves, no involucre, 

 involucels mostly present, and yellow, white, or purple flowers. Calyx-teeth 

 obsolete (very rarely evident). Fruit strongly flattened dorsally, oblong to 

 orbicular. Carpel with filiform and approximate dorsal and intermediate ribs, 

 and winged laterals coherent till maturity with those of the other carpel; peri- 

 carp thin, with strengthening cells beneath each rib and nerve; stylopodium 

 wanting; oil-tubes one to several in the intervals (rarely obsolete), 2-10 on 

 the cornrnissural side. Seed dorsally flattened, with plane" face (rarely slightly 

 concave) . Peucedanum, 



