46 
SeUmini, with which genus it is very closely allied. The chief differences 
are the more decidedly dorsally flattened fruit, less prominent (not winged) 
dorsal and intermediate ribs, laterals broadly winged, and thick conical 
stylopodium, numerous small oil tubes, and concave seed-face of Coniose- 
linum. Our species is related to SeUmim through S. Hookeri, which 
it very closely resembles. 
1* C. Cana,d6nse Torr. & Gray, FI. i. 619. One to five 
feet high, glabrous except the somew'hat puberulent Inflorescence: 
leaves often very large, with Inflated petioles, 2 to 3-pinnate (or 
the primary divisions apparently ternate in the larger leaves), the 
ovate acute segments an inch or more long, laciniately lobed: um- 
bel 10 to 20-rayed; rays about an inch long; pedicels 3 to 4 lines 
long: fruit 2 to 2^ lines long. (Fig. 23 .) — Selirmm Canadense 
Michx. FI. i. 165. 
Swamps and cold cliffs, from the mouth of the St. Lawrence {Michaux) 
to Vermont and Minnesota, and extending southward into Illinois, Indiana, 
and Missouri; also along the highest mountains as far south as North 
Carolina. PI. August to October. The stations reported from the United 
States are as follows: Yeimont {Ttilly, Pringle), Massachusetts (Oa/£ea), 
New York {Kneiskern, Hoysradt, Dudleyf, Pennsylvania {Porter), North 
Carolina {Gray & Carey), Indiana {Rose), Illinois {Vasey), Missouri 
{Tracy, Broadhead), Iowa {Arthur), Minnesota {Garrison), Wisconsin 
{Lapham), and Michigan {Wheeler & Smith); also in the mountains of 
Colorado, where it is confused with Ligusticuni scopulorum. Apium 
bipinnatum Walter has also been very doubtfully referred to this species, 
but Walter’s plant is altogether uncertain, and his locality is a presumptive 
evidence against such reference. 
10. TIEDEMANNIA DC. Mem. Umbel 51. — Smooth 
erect swamp herbs, with fascicled tubers, leaves simply pinnate or 
ternate or reduced to petioles, involucre of few bracts or none, in- 
volucels of numerous small bractlets or none, and white flowers. 
— Inch Archemora DC. 
Bentham & Hooker have included both Tiedemannia and Archemora 
under Peucedanum. Their habit and habitat are totally different from our 
species of Pe^(cedaJ^'am, which are low dry ground western forms, with 
much dissected leaves, and roots never fasciculate-tuberous. The fruit 
characters are no less distinguishable, that of Tiedemannia being less 
flattened than ' in Peucedanum, with a thick conical stylopodium, and 
always appearing to have 5 filiform dorsal ribs (owing to the prominent 
inner marginal nerves of the lateral wings). In Peucedanum when the 
lateral wings are nerved it is always on the commissural side as in Lepto- 
tcenia. These characters, which serve so well to separate Tiedemannia 
