27 
obtuse very prominent ribs, a small group of strengthening cells 
in each; the narrow commissure prominently corky-thickened, 
partly divided by a groove. Stylopodium depressed or wanting. 
Oil-tubes large, 2 on the commissural side. Seed-section nearl} 
round. 
(b). Eibs filiform, with prominent strengthening cells. 
Aletes. Calyx-teeth prominent. Fruit oblong, gla- 
brous. Carpel with equal and prominent ribs. Stylopodium de- 
pressed. Oil-tubes large and solitary in the broad intervals, 2 on 
the commissural side, and a small one in each lib. Seed sulcate 
beneath the oil-tubes, with face plane or slightly concave. Acau- 
lescent mountain plants. 
49. Zizia. Calyx-teeth prominent. Fruit ovate to oblong, 
glabrous. Stylopodium wanting; styles long. Oil-tubes large 
and solitary in the broad intervals, 2 on the commissural side, and 
a small one in each rib. Seed terete, sulcate beneath tire oil-tubes. 
Caulescent prairie and meadow plants. 
(5). Fruit with plane seed-face, conical stylopodium, and solitary oil- 
tubes. 
50. Carum. Calyx-teeth small. Fruit ovate or oblong, 
glabrous. ' Carpel with filiform or inconspicuous ribs, without 
stren<ythenino' cells. Oi.-ducts 2 to b on the commissural side. 
Seed dorsally fl.tttened, more or less sulcate beneath the oil-tubes; 
the face plane or slightly concave. 
51. Cicuta. Calyx-teeth rather prominent. Fruit oblong 
to nearly orbicular, glabrous. Carpel with strong flattish corky 
ribs, the laterals largest, without strengthening cells. Oil-tubes 2 
on the commissui’al side. Seed nearly terete or somewhat 
dorsally flattened. 
52. Cryptotaenia. Calyx-teeth obsolete. Fruit linear- 
oblong, glabrous. Carpel with obtuse equal ribs, each subtended 
by a very broad group of strengthening cells (2 groups also on the 
commissural side). Stylopodium slender conical. , Oil-tubes soli- 
tary beneath each rib (as well as in the intervals), 2 to 4 on the 
commissural side. Seed somewhat sulcate beneath the oil-tubes. 
53. Leptocaulis. Calyx-teeth obsolete. Fruit ovate, 
