Cypripedium L., 1753

D. M. Moore (ed.), 1980, CCIII Orchidaceae, Flora Europaea, Vol 5: Alismataceae to Orchidaceae, Camebridge: Cambridge University Press, pp. 325-350 : 326

1. Cypripedium L. 1

Plants with creeping rhizomes. Stems with 2-4 leaves. Flowers solitary, rarely 2(-3), large. Perianth-segments patent; outer median ovate to elliptical, erect, the outer lateral connate in basal half; inner oblong to lanceolate, often twisted. Labellum

large, concave, inflated, slipper-shaped; spur absent. Column stout, surmounted by large petaloid sterile anther partly closing mouth of labellum. Stigmas peltate; rostellum absent. Viscidia absent; bursicles absent.

1 Stem with 2 leaves; median outer perianth-segment 1 -8-2-8 cm

3. guttatum

1 Stem with 3-4 leaves; median outer perianth-segment 3*5—6 cm

2 Labellum yellow, distinctly shorter than other perianth-

segments 1. calceolus

2 Labellum pinkish to purplish, not or slightly shorter than other perianth-segments 2. macranthos