AMMIACEAE 875 



a conic stylopodium. 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. Seeds much flat- 

 tened dorsally. [ Tiedemannia DC. ] 



Leaves reduced to hollow, terete, transversely-jointed petioles (phyllodes). 1. O.flliformis. 



Leaves with simple, pinnate or palmate blades. 



Leaf-blades simple, or of 3 palmately disposed leaflets at the end of an elongated 



petiole. 2. 0. ternata. 



Leaf-blades pinnately divided. 



Leaflets conspicuously elongated, less than 3 mm. wide : fruit 4 mm. long. 3. 0. longtfolia. 



Leaflets not conspicuously elongated, over 3 mm. wide : fruit 5-6 mm. wide. 4. 0. rigiaior. 



1: Oxypolis filifdrmis (Walt.) Britton. Stems 5-18 dm. tall, simple or branched 

 above : leaf-blades reduced to elongated hollow jointed phyllodes, 0.3-6 dm. long, attenuate : 

 bracts of the involucres linear-subulate : umbels 3-10 cm. broad : rays slender, 6-16, 2-7 

 cm. long : corolla white, about 2 mm. broad : pedicels 4-8 mm. long : fruit oblong-oval or 

 oval-obovate, 5-6 mm. long, broadly winged ; oil-tubes one in each interval, and 2-4 in 

 the commissural side. [Tiedemannia teretifolia DC.] 



In swamps, Virginia to Florida and Louisiana. Summer and fall. 



2. Oxypolis ternata (Nutt.) Heller. Stems 5-9 dm. tall, usually somewhat 

 branched : leaf-blades entire or divided into 3 elongated linear or filiform entire leaflets : 

 umbels 3-10 cm. broad : rays very slender, 2-6 cm. long, ascending or curved upward : 

 corolla white, 2-2.5 mm. broad : fruit oblong, 4-5 mm. long, winged, rather delicately 

 ribbed. 



In low pine lands, North Carolina to Florida. Fall. 



3. Oxopolis longifolia (Pursh) Small. Similar to 0. riyidior in habit. Leaves 

 with conspicuously elongated entire leaflets less than 3 mm. wide : umbels few-rayed : fruit 

 4mm. long. [Sium longifolium Pursh.] 



In low grounds and swamps, New Jersey to South Carolina and Tennessee. Summer and fall. 



4. Oxypolis rigidior (L. ) Raf. Stems 5-18 dm. tall, nearly simple or widely 

 branched : leaf-blades pinnately divided ; leaflets 3-9, thinnish, linear to oblong or 

 lanceolate, acute or acuminate, 3-12 cm. long, entire or sharply toothed or incised : umbels 

 5-15 cm. broad : rays 7-25, 2-10 cm. long : corolla white, 3-3.5 mm. broad : fruit oblong 

 or oval, 5-7 mm. long, winged ; oil-tubes 1 on each interval, 4-6 on the commissural side. 



In swamps or on wet banks, New York to Minnesota, Florida and Louisiana. Summer and fall. 

 COW-BANE. WATER DROPWORT. 



40. LOMATIUM Raf. 



Perennial herbs, with tuberous or thick roots, often acaulescent. Leaves basal : blades 

 pinnate, ternate, or more or less finely dissected. Flowers in compound umbels. In- 

 volucres wanting. Involucels of several or many bractlets. Hypanthium truncate, or nearly 

 so. Petals white or variously colored. Disk with a depressed stylopodium, or flat. Fruit of 

 various shapes, dorsally flattened : carpels with slender dorsal and contiguous ribs and 

 lateral wings : oil-tubes usually 1-4 in the intervals and 2-10 in the inner side. 



1. Lomatium daucifolium (Nutt. ) Coult. & Hose. Foliage tomentose, less densely so 

 in age. Stems very short : leaves clustered at base ; blades 5-15 cm. long, finely dissected, 

 the ultimate segments narrowly linear or filiform : peduncles usually overtopping the leaves, 

 -2 dm. tall : umbels irregular, 2-10 cm. broad : rays 3-20, stoutish, 2.5-8 cm. long, those 

 of the same umbel very variable in length : fruit broadly oblong, 5-8 mm. long, the wings 

 $ as wide as the body, glabrous ; oil-tubes 1-3 in each interval, and 2-4 on the commissural 

 side. 



On prairies, Missouri to Nebraska and Texas. Spring. 



41. PASTINACA L. 



Annual or biennial herbs, with thick conic roots and heavy scented. Leaves alternate : 

 blades pinnately compound ; leaflets toothed or lobed. Flowers perfect, in compound 

 umbels. Involucres and involucels usually wanting. Hypanthium truncate. Petals yellow. 

 Disk with a depressed stylopodium. 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. Seeds flat. WILD PARSNIP. 



1. Pastinaca sativa L. Biennial, glabrous below. Hoot narrowly conic, strong- 

 scented : stems 6-20 dm. tall, simple or widely branched, sharply ridged : leaf-blades 



