Cypripedium calceolus

Bergstrom, G., Birgersson, G., Groth, I. and Nilsson, L. A. 1992. Floral fragrance disparity between three taxa of lady s shpper Cypripedium calceolus (Orchidaceae). Phytochemistry 31 2315-2319. 

N.A. Cypripedium calceolus L. C. pariflorum var. pubescens C. calceolus L. var. pubescens Cypripedin, tannic acid, gallic acid.100 Treat headache, nervousness, anodyne, antispasmodic, sedative. 

Comus florida, Cypripedium calceolus, C. pariflorum, Glycyrrhiza glabra, Rumex acetosella, R. aquaticus,... 

In this example, we examine differences in the floral aroma chemistry of three species of Cypripedium as determined by Bergstrom et al. (1992). Before the recognition of the North American species (C. parviflorum with two or three varieties), C. calceolus L. was thought to consist of three entities, whether varieties or subspecies is not relevant, the European calceolus, and two North American entities, parviflorum and pubescens. ... 

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