THE FEKTILISATION OF SALVIA AND OTHER FLOWERS. 273 
form the landing-place. The anther is now just in the mouth 
of the opening into the nectary, and a bee cannot get at the 
sweet fluid without striking against it ; in which case it will get 
smeared with the pollen grains. Some of the pollen will also 
fall into the glandular cavity, and this also will afterwards 
adhere to the proboscis of the insect as it sucks up the fluid. 
As soon as all the pollen is shed the stamen falls back into 
its old position, and another stamen takes its place, and so on 
till all the stamens in succession have gone through the same 
order of changes. Then, and not till then, the pistil with its 
stigmas ripens, and as the carpels lengthen the stigmas come to 
occupy the same position in the interpetalous fissure, as was 
previously occupied by the successive anthers. A bee in getting 
at the nectary will now strike upon the stigmas, and if it have — 
as is probable — pollen grains on its proboscis, will leave these 
adherent to the viscid surface ; and thus, as in the other plant 
I have described, the more mature blossoms are fertilised by the 
pollen of the younger ones. 
The fertilisation once completed, all the paraphernalia con- 
structed to bring this result about are thrown aside, as no longer 
of use. The glandular petals, the sepalous receptacle of the 
fluid, the landing-stage, all fall off, and the plant is spared the 
cost of their further maintenance. 
The preceding paper was written in the summer of 1868. 
At that time I thought I was the first to have discovered the 
purport of the strange structure of the stamens in salvia. I 
learnt later from Mr. Darwin — naturally somewhat to my disap- 
pointment — that this was not the case; but that already two 
years earlier Hildebrand had published an extensive series of 
1 observations on salvia, in which the structure was fully explained. 
On reading Hildebrand’s pamphlet, I found not only that this 
was as Mr. Darwin had told me, but that, even long ago, the main 
fact had been noted by Sprengel. I have, however, thought it 
well to publish my own observations for several reasons. In the 
first place, Hildebrand’s paper is so little known apparently, 
i that I can find no allusion to it in any English or French manual 
of botany. The curious anatomical structure of the stamen is 
described in all of them, and often is figured, but not a word is 
; said of its physiological significance. A second reason is, that 
there are numerous minor points, which seem to me of much 
i interest, which have been passed over by Hildebrand. 
T 2 
