i64 NATIVE BRITISH ORCHIDACEiE 



but of aphides infesting it, may throw Hght on the visits of Sarcophaga camosa, a fly 

 which frequents decaying animal matter, to the flowers of Epipactis palnstris, which 

 so puzzled Darwin. Mr Burton was a most successful cultivator of British orcliids. 

 Spikes of A. anthropophora were exposed at Challes-les-Eaux, Savoie, France, m 

 May, 1929, together with Ustera ovata, Cephalanthera grandiflora, five species oi Orchis 

 and four of Ophrys. The following Hymenoptera came (in very small numbers) and 

 visited one or other (rarely more than one) of the above species: Hive-bees, Bombi 

 (two species), Ualktus (three species), Andrena (two species), Bucera tuhemdata, 

 Gorytes mjstaceus; also the following Diptera, Echinomjia magnkornis and Volucelk 

 inflata. Not one of these took the shghtest notice of Aceras anthropophora. 



Genus XX ORCHIS L. 



Column erect, surmounted by the non-detachable anther. Stigma central, on front 

 of column, which forms roof of spur-entrance. Pollinia tv/o, caudicles attached to 

 separate viscidia, enclosed in the same pouch. 



Herbs with entire or forked tubers, enthe glabrous leaves, numerous rather small 

 flowers in a spike, connivent or spreading sepals, 3-lobed lip and honeyless spur 

 with liquid between its walls. 



Orchis L., Gen.pl. ed. i, p. 270; ed. 5, p. 405 (1754)- 

 By far the largest genus of European orchids, and except Ophrys, the most highly 

 developed and speciahsed. About 80 species are known, inhabiting Europe, temperate 

 Asia, N. Africa, the Canary Islands, and (three species) the United States and Canada 

 (Oakes Ames, Orchids of the United States and Canada, p. 83 (1924)), but according 

 to Schlechter these latter constitute a separate genus. 



Fertilisation. See "Pollination and Fertilisation", p. 21. 



KEY TO SPECIES 



A. Tubers entire (Euorchis Klinge) 



Section I Herorchis Lindl. 



Sepals and Petals forming a helmet. 



Sub-section i Militares Pari, 

 Lip anthropoid, mid-lobe bi-lobed, longer than side-lobes. Bracts short, mem- 

 branous. Sepals more or less coherent. 

 I. Helmet greyish, flushed violet or rose; side and terminal lobes of hp violet or 

 rose-red, long, narrow, of similar shape. O- simia 



