Sium suave Walter

Sium suave
Add the synonyms:
Sium helerophylum Raf. Herb. Raf. 69. 1833. (Nomen nudum.) Siumis helerophyla Raf. New Fl. 4: 31. 1838.

Sium suave Walt. Fl. Car. 115. 1788
Sium cicutaefolium Schrank, Baier. Fl. 1: 558. 1789.
Sium lineare Michx. Fl. Bor. Am. 1: 167. 1803.
Cicuta daurica Fisch. Cat. Jard. Gorenki ed. 2. 45. 1812. (Nomen nudum.)
Sium lenuifolium Muhl. Cat. 31. 1813.
Crilamus dauricus Hoffm. Gen. Umbell. ed. 2. 184. 1816.
Sium rugosum Raf. Med. Fl. 2: 264. 1830 (hyponym) ; Atl. Jour. 151. 1832.
Falcaria dahurica DC. Prodr. 4: 110. 1830.
Sium cicutarium W. Baxter in Loud. Hort. Brit. Suppl. 4: 639. 1850. (Hyponym.)
Apium cicutaefolium Benth. & Hook.; Forbes & Hemsl. Jour. Linn. Soc. 23: 328. 1887.
Sium cicutaefolium var. brevifolium Peck, Ann. Rep. N. Y. State Mus. 43: 83. 1890.
Sium helerophvllum Greene, Pittonia 2: 102. 1890.
Sium cicutaefolium var. helerophvllum Jepson, Fl. W. Middle Calif. 353. 1901.
Drepanophyllum lineare K.-Pol. Bull. Soc. Nat. Mosc. II. 28: 181. 1915.
Sium cicutaefolium var. lineare H. Wolff in Engler, Pflanzenreich 90 (4 229 ) : 57. 1927.
Sium latifolium of American authors, not 5. latifolium L. 1753.
Plants stout, 6-12 dm. high, from fusiform, fascicled roots; leaves oblong to ovate in general outline, excluding the petioles 6-25 cm. long, 7-18 cm. broad, pinnate, or rarely simple and serrate and incised, the leaflets lanceolate to linear, 1-4 cm. long, 3-15 mm. broad, distinct, remote, the lower frequently obsolete, finely serrate to coarsely serrate or incised; petioles stout, often fistulose, 1-8 dm. long; peduncles stout, 4-10 cm. long; involucre of 6-10 lanceolate or linear bracts, 3-15 mm. long, acute, entire or incised, unequal, reflexed; involucel of 4-8 linear-lanceolate bractlets, 1-3 mm. long, acute, entire; rays 10-20, slender, subequal, 1.5-3 cm. long; pedicels 3-5 mm. long; calyxteeth minute; halves of the carpophore adnate to the mericarps; fruit oval to orbicular, 2-3 mm. long, 2-2.5 mm. broad.
Type locality: Presumably "Carolina," Waller.
Distribution: Swamps; Newfoundland to Virginia, west to British Columbia and central

Sium floridanum Small, Man. SE. Fl. 976. 1933
Plants slender, about 3 dm. high; leaves ovate in general outline, excluding the petioles 8-15 cm. long, 7-14 cm. broad, pinnate, the leaflets broadly lanceolate, 2-7 cm. long, 1-2 cm. broad, distinct and remote, finely appressed-serrate, the terminal leaflet often ovate; petioles about 5 cm. long; peduncles slender, 1-4 cm. long ; involucre of 2-5 linear, acute bracts, 2-5 mm. long; involucel of bractlets similar to the bracts, 1-2 mm. long; rays 6-10, filiform, 6-15 mm. long, unequal; calyxteeth minute; immature fruit oval to orbicular.
Type locality: Swamps of the Chipola River, Florida, Chapman. Distribution: Known only from the type locality.