Cypripedium L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1980, Flora Europaea. Volume 5. Alismataceae to Orchidaceae (Monocotyledones), Cambridge: Cambridge University Press : 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 By D. M. Moore. 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