EPIPACTIS 85 



Darwin describes thus: "As some plants grew close to my 

 house, I have been able to observe here and elsewhere their 

 manner of fertilisation during several years. Although live 

 bees and bumblebees of many kinds were constantly flying 

 over the plants, I never saw a bee or any Dipterous insect 

 visit the flowers; but in Germany Sprengel caught a fly 

 with the pollinia of this plant attached to its back. On the 

 other hand, I have repeatedly observed the common wasp 

 (^Vespa sylvestrts) sucking the nectar out of the open cup- 

 shaped labellum. I thus saw the act of fertilisation affected 

 by the pollen masses being removed by wasps, and afterward 

 carried attached to their foreheads to other flowers. 

 It is remarkable that the sweet nectar of this Epipactis 

 should not be attractive to any kind of bee. If wasps were 

 to become extinct in any district, so probably would the 

 Eptpactts latifolia." 



Possibly the scarcity of our American species, Epipactis 

 viridiflora, is due to the fact that its own particular insect 

 servitor has grown more scarce. Hive bees visit another 

 English species of Epipactis, for Darwin's son, William, saw 

 them in the Isle of Wight visiting about a score of flowers, 

 and many of them had pollen masses attached to their fore- 

 heads. He also noticed that the elastic character of the 

 hinged lip which tended to spring up as the bees left the 

 flowers seemed to make the bees fly upward in such a way 

 as to strike against the knob of the rostellum. Darwin 

 asked a friend to try an experiment to see whether this 

 hinged lip was an advantage to the flower; accordingly 



