Æ. Podagrària, L., a common and troublesome weed in Europe, is reported from R. I. to Del. and E. Penn.
Calyx-teeth obsolete. Fruit very small, ovate, usually bristly or tuberculate, with somewhat prominent ribs; oil-tubes solitary in the intervals; stylopodium conical; seed-face plane or somewhat concave.—Very slender smooth branching annuals, with finely dissected leaves (segments filiform or linear), and small white flowers in very unequally few-rayed pedunculate umbels. (Name from λεπτός, slender, and καυλός, a stem.)
1. L. divaricàtus, DC. Plant 1–2° high, with branches and umbels diffusely spreading, the very slender rays ½–1´ long and the longer pedicels often 3–6´´ long; fruit tuberculate, ½´´ long. (Apium divaricatum, Benth. & Hook.)—N. C. to Fla., west to Ark. and Tex.; reported from Kan. April.
2. L. pàtens, Nutt. Of similar habit, but the umbels shorter and more strict, the rays 3–6´´ long or less and the pedicels short; fruit densely sharp-tuberculate or nearly smooth. (Apiastrum patens, Coult. & Rose.)—Central Neb. to Tex. and N. Mex.
29. DISCOPLEÙRA, DC. Mock Bishop-weed.
Calyx-teeth small or obsolete. Fruit ovate, glabrous; carpel with dorsal ribs filiform to broad and obtuse, the lateral very thick and corky, those of the two carpels closely contiguous and forming a dilated obtuse or acute corky band; oil-tubes solitary, stylopodium conical; seed nearly terete.—Smooth branching annuals, with finely dissected leaves, involucre of foliaceous bracts, involucels of prominent or minute bractlets, and white flowers. (Name from δίσκος, a disk, and πλευρόν, a rib.)
1. D. capillàcea, DC. Plant 1–2° high (or even 5–6°); leaves dissected into filiform divisions; umbel 5–20-rayed, involucre of filiform bracts usually cleft or parted, and involucels more or less prominent, fruit 1–1½´´ long, ovate, acute.—Wet ground, Mass. to Fla., west to Ill., Mo., and Tex. June–Oct.
2. D. Nuttàllii, DC. Similar in habit; involucral bracts short and entire; fruit very small (½´´ long), as broad as high, blunt.—Ill. (?) to Ark., La., and Tex.
30. CONÌUM, L. Poison Hemlock.