1^6 NATIVE BRITISH ORCHIDACE^ 



PlABiTAT. Grassy calcareous slopes or cliifs, chalk downs, rather dry meadows and 

 pastures. More frequently a plant of the mountains or hills. Flowers June to July. 

 Distribution. Widely distributed, but local, and usually rare. In Kent fairly 

 frequent in some districts.^ Webster says that on some Kentish hills it is very 

 abundant, and quite enlivens the landscape. Isle of Wight and southern counties 

 to Northumberland and Cumberland, in widely scattered localities. Europe from 

 Scandinavia and Mid-Russia to Northern Spain, Italy, the Balkans, and Caucasus; 

 Urals, Siberia. 



Orchis ustulata L., Sp. pi. ed. i, p. 941 (i753)- Ophrys anthropophora, 

 Fl. Danica (1763), not L. Orchis amcena Crantz (1769). O. parviflora 

 Willd (1805). HiMANTOGLOSSUM PARViFLORUM Sprengel (1826). The last 

 name looks as if Sprengel also may have found a spike in which the viscid discs 

 were adherent, as he placed it under Himantoglossum. 



Fertilisation. Hermann MuUer, that prmce of observers of the fertilisation of 

 flowers, says^ that the very narrow entrance to the spur indicates that butterflies 

 visit the flowers, the crimson spots and contrast of colour between the helmet and 

 the lip pointing to day-flying Lepidoptera, whilst the sweet smell and the wliiteness 

 of the lip probably also attract night-flyers. He did not succeed m seeing the flowers 

 visited, and there appears to be no record of any other observer having done so. 



The arrangements for pollination somewhat resemble those of Anacamptis pjra- 

 midalis. The erect converging guiding plates of the latter are replaced by the deep 

 groove at the base of the lip, wliich answers the same purpose. There are also two 

 lateral stigmas, as in pjramidalis, but these are connected by a narrow rim of true 

 stigmatic tissues The downward motion of the polHnia is rapid, taking place in 

 about 15 seconds, and they also diverge sUghtly, so that their tips become wider 

 apart, and are thus in position to touch the separated stigmas of the next flower 

 visited. They are, however, often shghtly divergent when first withdrawn. 



On May 9th, 1929, I was watching some orchids at Challes-les-Eaux, Savoie, 

 France, in the forenoon, when a large fly, Echimmjia magnicornis Meigen, alighted 

 on the top of a spike of O. ustulata, and began tlirusting his proboscis mto the flowers, 

 working downwards. I netted him, but did not expect that he could have removed 

 any poUinia, owing to his upside-down position. I was surprised to find a bunch 

 of eight pollinia attached to the under-surface of his jointed proboscis, near the base 

 of its apical half, just above the joint. He had thus visited at least four flowers. 



If 0. ustulata is usuaUy pollinated by this insect, or by other allied Diptera which 

 visit the flowers in a similar manner, it would account for the unusual coloration 

 of the spike, for the dark-coloured apex of the Burnt Orchid is conspicuous and 



