UMBELLIFERAE (PARSNiP FAMILY) 363 



Flowers yellow. 



Roots tuberous or moniliform. 



Umbellets open; pedicels slender C. ambigua. 



Umbellets compact; fruit nearly sessile 2, C, leptocarpa. 



Roots more or less thickened. 



Plant glabrous or nearly so; fruit glabrous. 



Oil-tubes several in the intervals • • • . 3. C. montana. 



Oil-tubes large and solitary. 



Glabrous throughout ' . . . , • • . 4. C. Grayi. 

 Slightly puberulent on the herbage ... . 5. C. bicolor. 



Plant pubescent, at least when young. 



Leaves finely dissected, ternate then pinnate. 



Bractlets of involucels lanceolate, conspicuous and united 



at base 6. C. foeniculacea, 



Bractlets linear, smaller, distinct 7. C. Jonesii. 



Leaves ternate or biternate, with long linear segments , S. C. platycarpa. 



Flowers white. 



Bractlets not searious 9. C. macrocarpa. 



Bractlets scarious-margined 10. C. orientalis. 



1. Cogswellia ambigua (Nutt.) Jones, Contrib. West. Bot. 12: 32. 1908. 

 Glabrous, from low acaulescent to 3 dm. high and caulescent, with tuber- 

 ous sometimes moniliform roots: petioles much dilated at base; leaves 

 once to twice pinnate, with more or less elongated linear leaflets, the upper 

 often more dissected: umbel unequally 8-18-rayed, with no involucels; rays 

 2.5-8.5 cm. long; pedicels 4-8 mm. long; flowers yellow: fruit narrowly ob- 

 long, glabroiis, 6-8 mm. long, 2 mm. broad, very narrowly winged; oil-tubes 

 solitary in the intervals, 2 (broad and thin) on the commissural side, — Wyo- 

 ming and Montana to Oregon. 



2. Cogswellia leptocarpa (Nutt.) Jones 1. c. 33. Acaulescent, becoming 

 3 dm. high, from deep-seated tuberous roots, glabrous: leaves ternate then 

 pinnate, the ultimate segments linear and usually much elongated: umbels 

 with few very unequal rays, and involucels of small linear bractlets; rays from 

 almost wanting to 7.5 cm. long; flowers yellow: fruit nearly sessile, forming 

 a dense cluster, linear, 9-10 mm. long, 2 mm. broad, with very narrow wings^; 

 oil-tubes solitary in the intervals. — Reported from Steamboat Springs, Col- 

 orado; mostly to the northwest of our range. 



3. Cogswellia montana Jones 1. c. 34. Acaulescent, from a slender or 

 somewhat enlarged and elongated rootstock, glabrous except the slightly 



Euberulent inflorescence, 5-20 cm. high: leaves usually twice pinnate, the 

 laflets shorfr-oblong, obtuse, much crowded: umbel unequally 3-8-rayed, 

 with involucels of distinct, obovate, more or less purplish bractlets; rays 4-30 

 mm. long; pedicels 2^ mm. long; flowers yellow: fruit oblong, glabrous, 

 5-6 mm. long, 2-3 mm. broad, with wings about half as broad as body; oil- 

 tubes several in the intervals. {Lomatium purpureum A. Nels. Bull. Torr. Bot. 

 Club 28: 226. 1931.) — ^The western Dakotas to Wyoming and Oregon. 



4. Cogswellia Grayi C. & R. Contrib. IT. S. Nat. Herb. 12: 450. 1909. Gla- 

 brous tfioughout, with peduncles 7.5-22.5 cm. long: leaves ternate then pin- 

 nately decompound, the ultimate segments linear-fiUform,' elongated or short- 

 cuspidate, exceedingly; nmnerous: umbel rather equally 6-16-rayed, with 

 involucels of distinct linear subulate bractlets; rays 2.5-7.5 cm. long; pedi- 

 cels 10-16 mm. long; flowers yellow: fruit oblong, 8-16 mm. long, 5-9 mm. 

 broad, with wings usually more than half as broad as body, and filiform dor- 

 sal and intermediate ribs: oil-tubes usually solitary in the intervals (some- 

 times 2 in the lateral intervals), 2-4 on the commissural side. — ^Frequent in 

 our range and westward to Oregon and Washington. 



5. Cogswellia bicolor (Wats.) Jones 1. c. 38. Caulescent or scarcely so, 

 1-4.5 dm. high, glabrous or slightly puberulent: petioles wholly dilated; 

 leaves ternate then pinnately decompound, the ultimate segments very nu- 

 merous and filiform: umbel very unequally 2-10-rayed, with involucels of 1-8 

 linear-subulate bractlets; rays 2.5-12.5 cm. long; pedicels short; flowers 

 yellow: fruit linear-oblong, glabrous, 10-12 mm. long, 2-5 mm. broad, with 

 very narrow wings and neSrly obsolete dorsal and intermediate ribs; oil- 

 tubes large and solitary in the intervals, 2 on the commissural side. — West- 

 em Wyoming and in Utah and Idaho. 



