102 NEOTTEiE. Chap. IV. 



observed the common wasp (Vespa syhestris) sucking 

 the nectar out of the open cup-shaped labellum. I 

 thus saw the act of fertilisation effected by the pollen- 

 masses being removed by the wasps, and afterwards 

 carried attached to their foreheads to other flowers. 

 Mr. Oxenden also informs me that a large bed of 

 E. purpwata (which is considered by some botanists to 

 be a distinct species, and by others a variety) was fre- 

 quented by " swarms of wasps." It is very 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 Epipaetis 

 latifolia. 



To show how effectually the flowers are fertilised, I 

 may add that during the wet and cold season of 1860 a 

 friend in Sussex examined five spikes bearing eighty-five 

 expanded flowers ; of these, fifty-three had the pollinia 

 removed, and thirty-two had them in place : but as 

 many of the latter were immediately beneath the buds, 

 a larger number would almost certainly have been 

 afterwards remowed. In Devonshire I found a spike 

 with nine open flowers, and the pollinia in all were re- 

 moved with one exception, and in this case a fly, too 

 small to remove the pollinia, had become glued to the 

 rostellum, and had there miserably perished. 



Dr. H. Miiller has published * some interesting 

 observations on the difference in structure and manner 

 of fertilisation, as well as on the intermediate forms 

 between Epipactis ruhiginosa, microphylla, and viridi- 

 flora. The latter species is remarkable for the absence 

 of a rostellum, and for being regularly self-fertilised. 

 Self-fertilisation here follows from the incoherent 

 pollen-grains in the lower part of the pollen-masses 



* ' Verliandl. d. Nat. Ver. f. Westfal.' Jahrg. xxv. III. Folge, v. BJ. 

 pp. 7-36. 



