64 UMBELLIPERAE. 



P. nuttallii DC. Stem 2-4 feet high; pedicels and involucels pubescent; 

 leaf-segments narrow, entire or lobed. Prairies and upland woods; May- 

 July; rather rare; Scott, Muscatine, Johnson, Story, Appanoose, Decatur, 

 Ringgold, and Montgomery counties. 



TH'ASPIUM Nutt. Perennials, with ternately divided leaves, and yellow 

 flowers. Involucre wanting. Involucels 3-leaved. Calyx 5-toothed. Stylo- 

 podium wanting; styles slender, exserted. Fruit oblong, ovoid, with promi- 

 nent wings; oil-tubes solitary in the intervals, 2 on the inner face of the car- 

 pels. 



T. barbinode Nutt. Stem 2-3 feet high, somewhat angular, striate, loosely 

 branched, somewhat pubescent on the joints or in the umbels; leaves 1-3-ter- 

 nate, mostly biternate: leaflets ovate, with cuneate base, coarsely serrate, 

 often cleft or parted; flowers light yellow; fruit broadly oblong, 5-7 winged. 

 Rich woods; May-June; probably common. 



FOENICULUM Adans. Biennials or perennials, with striate stems, leaves 

 biternately dissected into numerous filiform segments, and yellow flowers. 

 Calyx-teeth obsolete. Involucre and involucels wanting. Fruit elliptic-ob- 

 long, subterete; ribs 5, prominent; oil-tubes solitary. Stylopodium large, 

 conic. 



f. officinale All. Whole plant aromatic; stem 4-6 feet high, purplish 

 green, somewhat glaucous. Waste places; July-September; rarely escaped 

 from cultivation; Johnson and Story counties. (F. foeniculum (L.) Karst.) 



PIMPINELLA L. Glabrous perennial, with ternately compound leaves, 

 involucre and involucels scanty or wanting, and yellow flowers. Calyx-teeth 

 obsolete. Fruit ovate to oblong, laterally compressed; ribs slender, equal; 

 oil-tubes numerous, 2-6 in the intervals. Stylopodium thick, broadly conic. 



P. integerrima (L.) A. Gray. Stem smooth, glaucous, 1-3 feet high; 

 leaves 2-3Hernate, leaflets ovate to lanceolate, entire; fruit broadly oblong; 

 stylopodium small or wanting. Rocky woods; May-June; common. 



ZIZIA Koch. Glabrous perennials, with undivided or ternately divided 

 leaves, and yellow flowers. Involucre wanting. Involucels of small bractlets. 

 Calyx-teeth prominent. Fruit glabrous, with slender ribs; oil-tubes large, 

 solitary, in the intervals and one in each rib. Stylopodium wanting. A 

 genus distinguished from Thaspium by the wingless fruit. 



Z. aurea (L.) Koch. Stem 2-3 feet high, radical leaves long-petioled, all 

 except the uppermost 2-3-ternate; leaflets ovate to lanceolate, sharply serrate, 

 sometimes incisely lobed or parted; rays 15-20; fruit oblong. Low grounds, 

 prairies and meadows; May-June; common. 



Z. cordata (Walt.) DC. Stem 2-3 feet high; lower leaves long-petioled, 

 ovate to orbicular, crenate, base deeply cordate, stem leaves short-petioled, 

 ternate or quinate, segments ovate or oval, crenate or lobed; rays 7-16; fruit 

 ovate or oval. Woods; May-June; Lyon county. 



ARALIACEAE Vent. Ginseng Family. 

 Ours perennial herbs or shrubs, with alternate pinnate leaves, and um- 

 bellate flowers. Petals not inflexed, valvate ia the bud. Styles usually 

 2-5. Ovary 2-5-celled; cells 1-ovuled. Fruit a 2-5-celled drupe. 



Aralia. Leaves alternate, decompound; styles 5. 



Panax. Leaves vertieillate, palmately 3-7-follolate ; styles 3-3, 

 ARALIA L. Herbs or shrubs from thick perennial roots. Flowers, white 

 or greenish, more or less polygamous. Calyx-tube adherent to the ovary, 

 limb 5-toothed. Petals 5, oblong, spreading, decid\ious. Stamens 5, alter- 



