UMBELLIFERAE (PARSNIP FAMILY) 357 



often appearing sessile, somewhat elongated in fruit: involucre inconspicuous, 

 hyaline, and lobed, sometimes reduced to a cup; invplucels conspicuous, the 

 bractlets distinct, obovate, entire, with very broad, white, and hyaline margins, 

 with more or less distinct green central region: pedicels shorter than the 

 bractlets: flowers white, sometimes purplish: fruit broadly oblong to nearly 

 orbicular, 6-8 mm. long, with broad, thin wings somewhat thickened at in- 

 sertion; oil-tubes 1-3 in the intervals, 4-8 on the commissural side: seed some- 

 what flattened, with broadly concave face. Cymopterus montanus. Kansas 

 to Dakota and west to Colorado and Wyoming. 



2. Phellopterus bulbosus (A. Nels.) C. & R. Contrib. Nat. Herb. 7: 168. 

 1900. Leaf-segments more crowded than in P. montanus: flowering umbel 

 more elongated, in fruit equaling or exceeding the leaves; involucre con- 

 spicuous, of broad hyaline bracts united at base; involucels more conspic- 

 uous, the broad hyaline bracts sometimes with a greenish central region; 

 pedicels longer than in P. montanus; flowers purplish: fruit oblong, much 

 narrower than in P. montanus, 8 mm. long, with broad thin wings not thick- 

 ened at insertion; oil-tubes 3-5 in the intervals, 6-10 on the commissural 

 side: seed face with rather deep and broad concavity. Green river region 

 of Wyoming. 



3. Phellopterus purpurascens (Gray) C. & R. 1. c. Peduncles longer than 

 in P. montanus, in fruit equaling or exceeding the leaves; umbels more or less 

 compacted; involucre conspicuous, composed of white or purplish hyaline 

 bracts which have 1-3 green or purplish nerves and are united at base, or 

 sometimes reduced to a hyaline sheath; involucels resembling the involucres: 

 flowers purple: fruit orbicular, with broad wings and oblong body 10-12 mm. 

 long : carpels somewhat flattened, with 5 broad, thin wings scarcely thickened 

 at insertion; oil-^tubes 2 or 3 in the intervals, 4 on the commissural side: seed 

 somewhat flattened, with broadly concave face. Mostly west of our range. 



3a. Phellopterus purpurascens Eastwoodae (Jones) C. & R. 1. c. 169. 

 More robust, 2-3 dm. high, with usually long peduncles: umbels and umbel- 

 lets more open, with prominent rays and pedicels: wings of fruit much nar- 

 rower, resulting in a narrow fruit. More eastern in range; central and western 

 Colorado. 



4. Phellopterus multinervatus C. & R. 1. c. Peduncles as in P. purpuras- 

 cens; involucre a low, hyaline more or less lobed sheath, or developing one or 

 more conspicuous bracts resembling those of the involucel; involucels con- 

 spicuous, composed of broad purplish bractlets united at base, which are 

 rounded at apex, many-nerved, and with narrow hyaline margins; flowers 

 purple: fruit orbicular, with very broad wings and oblong body, 12-15 mm. 

 long: carpels somewhat flattened, with 5 broad thin wings more or less thick- 

 ened at insertion; oil-tubes 2-4 in the intervals, 8 on the commissural side: 

 seed somewhat flattened, with broadly concave face. (P. camporum Rydb. 

 Bull. Torr. Bot. Club 31: 574. 1904.) Colorado and New Mexico and west 

 to Utah and Arizona. 



19. PTERYXIA Nutt. 



Plants of acaulescent habit or nearly so, and clothed at base with persist- 

 ent leaf-sheaths, leaves clustered at base with main divisions ternate then 

 pinnately finely dissected into short-linear more or less pungent segments, 

 mostly no involucre, involucels of narrow bractlets (not at all hyaline), and 

 yellow flowers. Calyx-teeth evident. Fruit oblong to orbicular in outline, 

 glabrous. Carpel usually strongly flattened dorsally, with wings thin through- 

 out, lateral ribs with broad wings, dorsal and intermediates from strongly 

 ribbed to broadly winged ; stylopodium wanting; oil-tubes several in the in- 

 tervals. Seed face plane or with a shallow and broad concavity. Cymopterus 

 in part. 



Flowers yellow; fruit oblong 1. P. calcarea. 



Flowers white; fruit orbicular 2. P. albiflora. 



1. Pteryxia calcarea (Jones) C. & R. 1. c. 173. Short caulescent, giving 



