CARROT FAMILY 615 



with ovate to lanceolate, serrate or incised leaflets; fruit ovate, 3 mm. long. 

 Wet meadows and open woods: Conn. Ga. Utah Ore. B.C. Plain 

 Submont. My-Au. 



2. Z. aurea (L.) Koch. Stems 3-10 dm. high; leaves all except the upper- 

 most twice or thrice ternate; leaflets ovate to lanceolate, sharply serrate, 2-10 

 cm. long; fruit oblong, about 4 mm. long. Fields and meadows: N.B. Fla. 

 Tex. Wyo. Mont. Sask. Plain Submont. My-Jl. 



17. MUSINEON Raf. 



Low glabrous or scabrous perennials, with thick elongated roots and dichoto- 

 mously branched stems. Leaves pinnately decompound, usually with more or 

 less winged rachis. Flowers yellow, rarely white, in long-peduncled umbels. 

 Bracts wanting; bractlets few and narrow. Calyx-teeth prominent. Stylo- 

 podium depressed. Fruit ovate or ovate-oblong, flattened laterally. Ribs 

 equal and filiform. Oil-tubes usually 3 in each interval, unequal in size, 2-4 on 

 the commissural side. Seed-face broadly concave. [Musenium Nutt.] 



Divisions of the leaves obovate or oblong, toothed; rachis dilated. 

 Fruit glabrous or slightly puberulent. 



Plant evidently caulescent; basal leaf-sheath not scarious, slightly dilated. 



1. M. divaricatum. 

 Plant with the stem above ground very short; basal sheath strongly dilated and 



scarious. 2. M. pedunculatum. 



Fruit strongly scabrous-puberulent. 



Divisions of the leaves obtuse. 3. M. tr achy sper mum. 



Divisions of the leaves acute or acuminate. 4. M. angustifolium. 



Divisions of the leaves linear or linear-oblong, entire; rachis not dilated; leaf-sheath 

 strongly dilated. 5. M. vaginatum. 



1. M. divaricatum (Pursh) Coult. & Rose. Stems ascending or decumbent, 

 1-2 dm. high; leaves bipinnatifid; segments obovate, 3-5-toothed; branches of 

 the umbels 10-25, 1-2 cm. long; pedicels very short; fruit 4 mm. long. Dry 

 ground: Sask. Neb. Colo. Alta. Plain Submont. My-Jl. 



2. M. pedunculatum A. Nels. Stem very short, less than 1 dm. high; 

 peduncles 1-2 dm. long; leaves thick, somewhat glaucous, bipinnate; the ultimate 

 divisions obovate, 2-5-toothed; rays of the umbels 10-20, 1.5-2.5 cm. long; fruit 

 45 mm. long. Clayey soil: Wyo. Submont. Je. 



3. M. trachyspermum Nutt. Perennial, with a thick fusiform deep-seated 

 root; stems decumbent or ascending, 0.5-2 dm. long, somewhat puberulent; 

 leaves bipinnatifid; divisions obovate, obtusish, 3-5-toothed; flowers yellow; 

 fruit 2-3 mm. long, scabrous-tuberculate, with prominent ribs. M. divaricatum 

 Hookeri T. & G. Dry plains: Sask. Neb. Colo. Alta. Plain Submont. 

 My-Jl. 



4. M. angustifolium Nutt. Stem decumbent or ascending, 1.5 dm. long 

 or less, puberulent; leaves bipinnatifid; rachis with very narrow wings; segments 

 lanceolate, acute, 3-5-toothed or cleft; fruit about 3 mm. long, scabrous-tubercu- 

 late, with rather prominent ribs. Sandy and gravelly plains: Sask. Colo. 

 Alta. Plain Submont. My-Jl. 



5. M. vaginatum Rydb. Stem less than 1 dm. high, glabrous; leaves 

 twice or thrice ternate; divisions linear or linear-oblong, obtuse, about 5 mm. 

 long; stem-leaves with a scarious-margined sheath; petals white or sometimes 

 yellowish; fruit oblong, 3 mm. long; seed-face plane. Mountains: Mont. 

 Wyo. Submont. Mont. Je-Jl. 



18. DAUCOPHYLLUM (Nutt.) Rydb. 



Low cespitose perennials, acaulescent or nearly so, with a branched caudex. 

 Leaves numerous, basal, or 1 or 2 cauline, pinnate or bipinnate, with filiform or 

 narrowly linear divisions. Flowers cream-colored to yellow, in dense umbels. 

 Bracts wanting; bractlets few, narrow, linear. Calyx-teeth prominent. Stylo- 

 podium wanting. Fruit ovoid or oblong, granular on the intervals. Ribs equal, 

 rather strong, but not at all winged. Oil-tubes 2 or 3 in the intervals, 4-6 on 

 the commissural side. Seeds terete or somewhat depressed; face plane. 



