Orchidaceae tS 
H. Flower spurred; spur 2 mm. or more long. 
I. Stem-leaves abruptly reduced to bracts; leaves withering at flowering; 
lateral sepals with base adhering to claw of lip; tubers rounded; spike 
spirally twisted. PIPERIA (p. 113) 
II. Stem-leaves gradually reduced to bracts; leaves not withering until fruit 
is formed; lateral sepals free; tubers elongated, root-like; spike not spiral- 
ly twisted. LIMNORCHIS (p. 114) 
HH. Flowers spurless. 
J. Leaves without whitish spots or lines; flowers in a dense spike which is 
somewhat spiral; lip not distinctly sac-like at base, with a horn-like pro- 
jection on each side near base. SPIRANTHES (p. 115) 
JJ. Leaves with whitish spots or lines; flowers in a loose spike or raceme 
which is not at all spiral; lip sac-like at base, without projections near 
base. 
K. Stem leafy at least below; perianth strongly purple-veined. 
EPIPACTUS (p. 115) 
KK. Leaves all basal; perianth not purple-veined. 
PERAMIUM (p. 115) 
CYPRIPEDIUM LADY’S-SLIPPER 
Glandular-pubescent, with coarse fibrous roots. Stem leafy or scapose. Leaves 
large, wide, many-veined, sheathing at base. Flowers in a leafy raceme or solitary, 
large, showy. Sepals spreading, separate or 2 of them united under the lip. Petals sim- 
ilar to the sepals but usually narrower; lip an inflated sac, the incurved margin auricled 
near the base. Column very short, incurved, bearing at each side an anther, and bearing 
above a dilated sterile petal-like stamen covering the summit of the style. Anther on a 
short filament or sessile; pollen-masses granular, without caudicle or gland. Stigma 
terminal, disk-like, wide, obscurely 3-lobed. (Gk. kypris—=Venus, pedilon—a shoe; the 
corolla is slipper-like. ) 
A. Stem with more than 2 leaves, 3—12 dm. high; lip 1.4 cm. or more long, color 
not as in AA; sepals and petals more than 2.5 cm. long (except in C. californicum). 
B. Lip white to rose, veined with purple. 
C. Flowers 1—3; sepals narrowly linear-lanceolate, 3.8—6.3 cm. long, brown- 
ish-sip2—-) cm. long. C. E: : 
C. montanum Dougl. (Large Lady’s-slipper) 
CC. Flowers 1—20; sepals widely oval, 1.2—4.2 cm. long, greenish-yellow; 
howte/——2.1 cm:slong. | U. C. 
C. californicum Kell. 
BB. Lip bright-yellow, 1.5—3 cm. long; flowers 1——-3; sepals ovate to ovate- 
lanceolate, 3—5 cm. long. E. 
C parviflorum Salisb. (Yellow Lady’s-slipper) 
‘AA. Stem with 2 nearly opposite leaves near its middle and | small lanceolate bract 
above them, 0.5——5 dm. high; lip 8—13 cm. long, greenish-yellow, with brown or 
purplish margins; sepals and petals 1.2—-2.5 cm. long. E. 
C. fasciculatum Kell. (Brown Lady’s-slipper) 
PIPERIA ORCHIS 
Roots rounded or tuber-like; stem leafy-bracted. Leaves usually withering or 
dead at time of flowering. Flowers small, greenish-white, in a terminal spike. Sepals 
and petals 1—-3-veined. Anther-cells parallel, opening at the side. Stigma a small 
beak between the anther-cells. 
