1887. | BOTANICAL GAZETTE, 289 
the exact spot which struck the stigma in the first place. 
When the insect visits another flower, the part to which the 
pollen is glued comes down upon the stigma. 
Cross-fertilization results from the fact that the stigma is 
labellum, and from the fact that only two or three flowers 
are open ata time. Guignard’s? opinion, that cross-fertiliza- 
tion is not so well assured as in Pogonia, no doubt, rests on 
an erroneous view of the floral mechanism. 
here is no nectar. If there were any real source of at- 
traction about the crest, small insects which are not heavy 
enough to depress the labellum would be the only ones to 
lictus, which visited the flowers, had their pollen-carrying 
hairs well filled, showing that they were on pollen-collecting 
expeditions. On the other hand, butterflies, whic 
visit flowers for pollen, paid no attention to the crest, but 
nard* saw a bumble-bee light upon the column of C. pulchel- 
lus, no doubt expecting to find nectar, while one which I 
Saw pull down the labellum had pollen in her baskets and 
evidently mistook the hairs for stamens 
ers a most convenient stage while sucking the sweets. 
Then the anther is behind them and the pollinia must become 
attached to their legs, as is the case with the milk-weed. 
But he did not see the thickened parts punctured by any in- 
_ S€ct, nor did he find pollinia on the legs of any. The thick- 
ened base of the lip seems to be intended to keep it from 
bending below the hinge, and that of the column to support 
the weight of an insect which falls upon it. From Guig- 
“Insects and Orchids,”’ J. A. Guignard, 16th Annual Report Bo Fe eit tae 
2 
-. Tn the 17th re = ive inte! 
‘port of the sam», p. 51, Guignard gives an in 
lerteation of the Cypripedium spectabile by Megachile melanophaea. 
* Loe, cit, 39, “ is 
4 
cit. 43. 
