Chap. I. ORCHIS PYEAMIDALIS. 23 



persons, and all have expressed the liveliest admiration 

 at the perfection of the contrivance by which this 

 Orchid is fertilised. 



As in no other plant, or indeed in hardly any 

 animal, can adaptations of one part to another, and 

 of the whole to other organisms widely remote in the 

 scale of nature, be named more perfect than those 

 presented by this Orchis, it may be w^orth while 

 briefly to sum them up. As the flowers are visited 

 both by day and night-flying Lepidoptera, it is not 

 fanciful to believe that the bright-purple tint (whether 

 or not specially developed for this purpose) attracts 

 the day-fliers, and the strong foxy odour the night- 

 fliers. The upper sepal and two upper petals form a 

 hood protecting the anther and stigmatic surfaces 

 from the weather. The labellum is developed into a 

 long nectary in order to attract Lepidoptera, and we 

 shall presently give reasons for suspecting that the 

 nectar is purposely so lodged that it can be sucked 

 only slowly (very differently from what occurs in most 

 other plants), in order to give time for the viscid 

 matter on the under side of the saddle to set hard 

 and dry. He who will insert a fine and flexible 

 bristle into the expanded mouth of the flower between 

 the sloping ridges on the labellum, will not doubt 

 that they serve as guides and effectually prevent the 

 bristle or proboscis from being inserted obliquely into 

 the nectary. This latter circumstance is of manifest 

 importance, for, if the proboscis were inserted ob- 

 liquely, the saddle-formed disc would become attached 

 obliquely, and after the compounded movement of the 

 pollinia they would not strike the two lateral stigmatic 

 surfaces. 



Then we have the rostellum partially closing the 

 mouth of the nectary, like a trap placed in a run for 



