284 Umbellaceae 
D. Plants low, 1—3 dm. high. 
E. Dorsal ribs of the carpels with wide wings. E. 
P. foeniculacea Nutt. 
EE. Dorsal ribs of the carpels with narrow wings. E. 
P. thapsoides Nutt. 
DD. Plants taller, 4 dm. or more high. U. 
P. californica C. & R. 
CC. Leaves of narrow outline. 
F. Pinnae of leaves small, distant. E. 
P. petraea C. & R. 
FF. Pinnae of leaves larger, more crowded. E. 
P. calcarea C. & R. 
AA. Flowers white. E. P. albiflora Nutt. 
AULOSPERMUM 
Caulescent or acaulescent. Leaves pinnately dissected, or ternately and then pin- 
nately dissected. Flowers white or yellow or purple; involucre usually none (present in 
ours) ; involucel-bracts small, exceeding the involucre-bracts (ours). Calyx-lobes evi- 
dent. Fruit oblong to orbicular, glabrous; carpel-wings 3—5, usually wide, thick at the 
insertion or not at all; stylopodium none; oil-tubes several in each interval (ours), 2 or 
more on the commissure side. (Gk. aulos—a tube; sperma—a seed; apparently from 
the numerous oil-tubes in the seed.) E. (Cymopterus glaucum.) 
A. glaucum ©. & R. ; 
CYMOPTERUS 
Plant dwarf, xerophytic; acaulescent. Leaves small, 1—3(ours)-pinnate. Flowers 
white or yellow, peduncles equaling or exceeding (ours) the leaves; involucre none (ours) ; 
involucel-bracts usually conspicuous and foliaceous, somewhat 3-cleft at apex (ours). 
Calyx-lobes present or none. Fruit flattened dorsally, ovate to oblong (ours), 10 mm. 
long (ours), glabrous (ours) or puberulent at the tip; dorsal and intermediate ribs filiform 
or winged; lateral wings wide, very thick, corky, coherent until maturity with those of 
the other carpel, forming a margin to the fruit usually thicker than the fruit-body; stylo- 
podium none; oil-tubes very small, |—8 in each interval, 2—14 on the commissure side. 
(Gk. kyma—a wave, pteron—a wing; the wings of the fruit are often wavy.) E. 
C. leibergii C. & R. 
RHYSOPTERUS 
Low, glabrous, on dry soil; stem short, slender, somewhat subterranean. [Leaves 
2—3 cm. long (ours), somewhat clustered at the stem-tip, |—2-pinnate, thick or coria- 
ceous; leaf-segments wide, of 3 leaflets each (ours); the lateral leaflets 2-lobed, the ter- 
minal 3-lobed. Flowers white; involucre none; rays stout (ours), 8—10 mm. long 
(ours) ; involucel-bracts rather conspicuous. Calyx-lobes evident. Fruit flattened later- 
ally, 3 mm. long (ours), nearly orbicular, glabrous; carpels flattened dorsally, boat- 
shaped, the margin and ends incurved; ribs 5, equal, prominent, obtuse, corky; stylopo- 
dium none; oil-tubes small, | in each interval, 2 on the commissure side. (Gk. rhysos—= 
wrinkled, pteron==a wing; referring to the fruit-wings.) E. 
R. plurijugus C. & R. 
