Chai. II. GYMNADENIA CONtPSEA. 67 



of the bristle. They then quickly become depressed so 

 as to lie in the same line with the bristle, — one a little 

 on one side, and the other on the other side ; and if 

 the bristle, held in the same relative position, be now 

 inserted into the nectary of another flower, the two 

 ends of the pollinia accurately strike the two protu- 

 berant stigmatic surfaces, situated on each side of the 

 mouth of the nectary. 



The flowers smell sweet, and the abundant nectar 

 always contained in their nectaries seems highly 

 attractive to Lepidoptera, for the pollinia are soon and 

 effectually removed. For instance, in a spike with 

 forty-five open flowers, forty-one had their pollinia 

 removed, or had pollen left on their stigmas : in 

 another spike with fifty-four flowers, thirty-seven had 

 both pollinia, and fifteen had one pollinium, removed ; 

 so that only two flowers in the whole spike had neither 

 pollinium removed. 



My son George went at night to a bank where 

 tliis species grows plentifully, and soon caught Plusia 

 chrijsifis with six pollinia, P. (jamma with, three, Anaitis 

 plac/iata with five, and Triphxna pronuba with seven 

 pollinia attached to their proboscides. I may add 

 that he also caught the first-named moth in my 

 flower-garden, with the pollinia of this Orchis attached 

 to its proboscis, but with all the jDollen-grains removed, 

 although the garden is a quarter of a mile distant from 

 any spot where the plant grows. Many of the above 

 moths liad only a single pollinium attached, somewhat 

 laterally to their proboscides ; and this would haj^pen 

 in every case, unless the moth stood directly in front 

 of the nectary and inserted it proboscis exactly be- 

 tween the two discs. But as the labellum is rather 

 broad and flat, with no guiding ridges like those on 

 the labellum of Orchis injramidalis, there is nothing to 



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