Mr A. D. Webster on the Fertilisation of Epipactis latifolia. 347 



On the Fertilisation o/Epipactis latifolia. By A. D. 

 Webster, Llandegai, Penrhyn. 



(Read 12tli November 1885.) 



Having during the past few years, but particularly the 

 sumnier of 1885, devoted considerable attention to the 

 above interesting subject, I have thought the following 

 observations not unworthy of record, as contributing to 

 a subject which, as yet, has received little investigation. 

 In the woodlands of this county (Carnarvonshire), where 

 tlie plant grows in unusual quantity, exceptional oppor- 

 tunities have been afforded me of studying it under various 

 conditions as to soil, altitude, and situation. 



All, or nearly all my observations tend to show (1) that 

 Epipactis latifolia is very imperfectly fertilised; (2), that, 

 although visited by insects, cross-fertilisation seldom takes 

 place; and (3) that self-fertilisation by the pollen falling 

 spontaneously on the stigma is not uncommon. 



1. That the plant is very imperfectly fertilised is 

 evident from the small quantity of seed produced. On 

 examining nearly one hundred plants when the seeds were 

 ripe in October, I was surprised at the small number of 

 capsules produced. (The ovules of unfertilised flowers 

 drop from the plant at an early date, thus affording an 

 unerring guide as to the difference between barren and 

 well-filied capsules.) 



I examined nineteen plants growing in consecutive order 

 in one wood, and out of a possible 492 capsules only 38 

 produced seed. Thinking that perhaps the density of 

 foliage or maritime situation might account for this 

 unusually small production of seed, I examined the plant 

 in quantity in two other warm, shady woodlands, but with 

 almost similar results. Sixteen plants, growing within a 

 short distance of each other, produced only 32 capsules 

 from 51 G flowers; while in another wood similarly situated 

 26 were produced out of a total of 215. This small 

 production of seed, in an unusually fine season like that 

 of 1885, clearly proves that Epipactis latifolia is very 

 imperfectly fertilised, and, as will be seen hereafter, that 

 cross-fertilisation by insect agency seldom takes place. 



