OrHBE^. Chap. I. 



CHAPTER I. 



OPHREiE. 



Structure of the flower of Oreliis mascula — Power of movement of the 

 poUlnia— Perfect adaptation of the parts in Orchis pyramidalis — 

 Other species of Orchis and of some closely allied generti — On the 

 insects which visit the several species, and on the frequency of their 

 visits — On the fertility and sterility of various Orchids — On the 

 secretion of nectar and on Insects being purposely delayed in 

 olitaining it. 



Thkoughout the following volume I have followed, as 

 far as I conveniently could, the arrangement of the 

 Orchideae given by Lindley. The British species 

 belong to five of his tribes, the Ophrese, Neottere, 

 Arethuseae, Malaxese and Cypripedese, but the two 

 latter tribes contain each only a single genus. Various 

 British and foreign species belonging to the several 

 tribes are described in the first eight chapters. The 

 eighth also contains a discussion on the homologies of 

 the flowers of the Orchideae. The ninth chapter is 

 devoted to miscellaneous and general considerations. 



The Ophrese include most of our common British 

 species, and we will begin with the genus Orchis. The 

 reader may find the following details rather diflBcult 

 to understand ; but I can assure him, if he will have 

 patience to make out the first case, the succeeding ones 

 will be easily intelligible. The accompanying diagrams 

 (fig. 1, p. 8) show the relative position of the more 

 important organs in the flower of the Early Orchis 

 (0. mascvia). The sepals and the petals have been re- 

 moved, excepting the labellum with its nectary. The 



