532 THE FERTILISATION OF FLOWERS. [PART ILI. 
the proper season, but on that occasion I found it visited by flies 
in considerable abundance, and several of the spikes were covered 
with spiders’ webs. I saw several specimens of Spilogaster cinerea, 
Wied., and a small species of Muscide alight on the labellum and 
suck the honey; but I did not see any of them touch the rostellum 
and remove the pollinia. After watching for a long time, I saw 
a larger yellow fly (Helomyza affinis, Mgn.) visit a flower; when 
it crawled up the labellum to its base, licking the honey on its 
way, it came in contact with the rostellum and cemented the 
pollinia to the anterior part of its thorax. It flew away, startled ; 
but it was caught in a spider’s web, and my chance of observing 
the fertilisation of Neottia was lost. 
Fig. 179.—Neottia nidus-avis, Rich. 
1.—Lateral view of flower. 
2.—Ditto, of labellum. 
8.—Labellum, from above. The small rings indicate honey-drops. 
4.— Essential organs, in side-view. 
br, bract; co, column. Other letters as in Fig. 180. 
Goodyera repens, R. Br—Mr. R. B. Thomson saw this plant 
fertilised in the north of Scotland by Bombus pratorum (Darwin, 
159, 165); I have seen it on the Alps fertilised by B. mastrucatus, 
% (609). 
The Alpine Chameorchis is probably adapted, like Listera, for 
fertilisation by Jchnewmonide (609). 
Epipactis latifolia, Swartz.—Charles Darwin observed this plant 
to be fertilised by wasps (Vespa silvestris). Self-fertilisation seems 
scarcely possible. 
Epipactis microphylla, Ehrh., fertilises itself regularly; but 
part of the pollen can be removed by insects by the aid of the 
sticky secretion of the rostellum, as the whole pollinia are in 
L. latifolia, 
Epipactis viridiflora, Rehb., has quite lost its rostellum, Small 
