AMMIACEAE. 213 



rays 2.5-7.5 cm. long: pedicels 10-16 mm. long: corolla white or greenish- 

 white: fruits oblong to oval-orbicular, 6-6.5 mm. long, glabrous. Occasional, 

 in low grounds. 



2. A. villosa (Walt.) B.S.P. Plants 6-18 dm. tall: leaflets 2-5 cm. long, the 

 blades thickish, oblong, oblong-lanceolate, or oval, 2-5 cm. long, serrate: 

 umbel-rays 2-5 cm. long: pedicels 3-4 mm. long: corolla white: fruits orbicu- 

 lar or orbicular-obovate, 4.5-5 mm. long, pubescent. Common, in dry thickets 

 and woods. 



19. OXYPOLIS Eaf. Perennial herbs. Leaf -blades pinnate or ternate, 

 or rarely reduced to hollow septate phyllodia. Umbels compound. Involucres 

 and involucels present. Sepals acute. Petals white. Fruit longer than broad, 

 dorsally flattened: carpels with the dorsal and contiguous ribs thin, and 

 winged lateral ribs, the latter nerved near the inner part of the wing: oil-tubes 

 solitary in the intervals and 2-6 in the inner face. 



1. O. rigidior (L.) Raf. Plants 5-18 dm. tall: leaves with relatively short, 

 often broad, leaflets; blades entire or saliently toothed, pale beneath: umbel 

 usually many-rayed: fruits oblong or oval, 5-6.5 mm. long, pale-winged. S. 

 Rare, in swamps. Schists. Sum. 



20. PASTINACA L. Annual or biennial herbs. Leaf -blades pinnately 

 compound. Umbels compound. Involucres and involucels usually wanting. 

 Sepals obsolete. Petals yellow. Fruit somewhat longer than broad, much 

 dorsally flattened: carpels with the dorsal and contiguous ribs slender, and 

 thin lateral wings: oil-tubes solitary in the intervals and 2-4 in the inner side. 



1. P. sativa L. Plants coarse, strong-scented, 6-20 dm. tall: leaf -segments 

 ovate or oblong, crenate-serrate, incised or lobed: fruits obovate, oval, or 

 orbicular-oval, 5-6 mm. long. Common, on roadsides and in waste places. 

 Nat. of Eu. Sum. WILD-PARSNIP. 



21. HEUACLEUM L. Perennial herbs. Leaf -blades ternately compound. 

 Umbels compound. Involucres and involucels of few, often deciduous, bracts 

 and bractlets or the former wanting. Sepals minute or obsolete. Petals 

 white, broadest above the middle, those of the outer and inner flowers different 

 in shape. Fruit usually longer than broad, strongly dorsally flattened: carpels 

 with the dorsal and contiguous ribs slender, and broadly winged lateral ribs, 

 the latter nerved near the outer edge: oil-tubes solitary in each interval, and 

 2-4 in the outer face, rarely extending beyond the middle of the carpel. 



1. H. lanatum Michx. Plants coarse and heavy-scented, 6-25 dm. tall: leaf- 

 blades 1-4 dm. long, the segments sharply toothed: umbel-rays 8-30, stout, 

 3-15 cm. long : fruits oval to obovate-oval, 8-12 mm. long. Common, in 

 fields and waste places. Sum. COW-PARSNIP. 



22. DAUCUS [Tourn.] L. Annual or biennial herbs. Leaf -blades pin- 

 nately decompound. Umbels compound. Involucres and involucels various, 

 or wanting. Sepals minute or obsolete. Petals white or rarely colored, often 

 unequal, broadest above the middle, inflexed at the apex. Fruit longer than 

 broad: carpels with 5 low primary ribs and 4 winged secondary ribs which are 

 also armed with a row of barbed bristles: oil-tubes solitary under the secondary 

 ribs and 2 on the inner face. CARROT. 



1. D. Carota L. Plants hispid, 4-12 dm. tall: leaf -segments very numerous: 

 umbel-rays many: corollas unequal in size and the central one often purple: 



