358 Mr A. D. Webster on the 



The flower rexnained open for twenty days, or until 12tli 

 June, when it collapsed. 



Fertilisation. — As regards fertilisation, I may state at 

 the outset that no native orchid on which I have experi- 

 mented is more difficult to understand, or has more com- 

 pletely baffled my observations than this. That Darwin's 

 description of the wonderful manner in which the pollen of 

 this orchid is removed by insects is true, I am, however, 

 well able to corroborate, for on several occasions I have 

 seen insects visit the flower by the large opening in the 

 labellum, and after repeated failure to get out by the same 

 way, owing to the inflected edges, at last force themselves 

 out by one of the two orifices close to the anthers, and in 

 doing so their backs were smeared with the glutinous pollen. 



This part of the work, the removing of the pollen, is 

 neatly enough performed, but how the pollen is to be 

 brought in contact with the stigma has pjuzzled me greatly. 

 It is quite evident that unless the same insect visits 

 another, or revisits the same flower, fertilisation cannot 

 take place, and from all my observations that such is likely 

 to occur is very improbable, although by no means impos- 

 sible, for the following reasons : — 



1. The difficulty of escape experienced by an insect that 

 visits the flower. 



2. Only those insects which experience the greatest 

 difficulty can remove the pollen. 



1. When an insect of sufficient size to remove the pollen 

 enters the labellum of the flower by the large opening at 

 the top, I have invariably noticed that its first aim is to 

 escape again, for a search after nectar seems out of the 

 question. In all cases that have come under my own notice, 

 the insect first tries, for several times in succession, to 

 escape by the way it entered, but the edges of the labellum 

 are incurved, and the numerous fine hairs within the 

 flower are pointed downwards from the edges on each side, 

 so that escape by scaling the sides is well-nigh impossible. 

 I have seen on difi'erent occasions several insects, after 

 much labour, ascend the edges of the labellum, but when 

 they came to the incurved edges, which may be considered 

 the special barrier, back they fell into the bottom of the 

 labellum. I have seen this repeated several times by the 



