G^roidh and Fertilisation of Cypripedium Caloeolus. 359 



same insect, until, tired and disgusted, the attempts to 

 escape by this way were given up. Next, the insect, 

 allured, no doubt, by the light emitted, through three 

 colourless, almost transparent lines at the upper end of the 

 labellum, crawls towards these, but by this way also finds 

 escape out of the question. These light lines, however, 

 have conducted the insect to near the upper end of the 

 labellum, and within a short distance of the two small 

 orifices, situated one on either side of the anthers. A 

 rush is now made for exit by this way, and as the hairs 

 here point in the opposite direction to those on the 

 flat sides of the labellum, the insect crawls easily up to the 

 small orifice, and after two or three attempts forces its 

 way out. In so doing it becomes smeared with the pollen, 

 with which it inevitably comes in contact, the anthers 

 being placed directly above the small orifices and under 

 the stigma. 



The pollen is so sticky and the orifices so small that 

 insects (small bees excepted) which come in contact with 

 the former are frequently unable to free themselves, and 

 so perish. Again, I have frequently found insects, that 

 were of too large a size to escape by these orifices, dead 

 within the labellum. 



Now, from these observations, it is hardly to be expected 

 that an insect, after once experiencing the difficulty of 

 escape from the labellum, would turn round and revisit the 

 same fiower or that on another plant ; indeed, in all the 

 instances that have come under my own notice, the insect's 

 escape from this temporary prison was quickly followed by 

 desertion of the locality in which the plants grew. 



That cross fertilisation is thus effected to any great 

 extent I cannot think ; and although Darwin and others 

 have seen insects visit the flowers of this Cypripedium, and 

 escape with pollen attached to their back, it is not on 

 record, and I believe no one has yet seen the same insect 

 visit another flower or revisit the same one. The tempta- 

 tions for insects to visit the flower are, likewise, small 

 indeed, for I have frequently watched for hours, during 

 bright sunny weather, when insect life was abundant, 

 their visits to the various alpine plants growing in close 

 contiguity, but rarely did one approach the score of 



