NOTES: ON THE FERTILISATION OF KNIGHTIA. 175 
transferred from the younger to the older flowers. It is natural 
to assume that this is done through the agency of insects, 
especially as the great abundance of honey induces many to 
visit the flowers. But in most cases they simply crawl 
Bipeut between the styles, and. never’ touch either the 
pollen or stigma elevated far above them. It appears 
to me that large insects only could aid in the work of fertilisa- 
tion ; and even among these the nocturnal or crepuscular moths 
could be of little service,.as the styles are far enough apart to 
allow of their proboscides being inserted without touching. 
Possibly some of the larger Diptera or Coleoptera, as well as the 
honey-bee (which is a regular visitant), may be of use; but the 
conclusion I have arrived at is that the flowers are principally 
adapted for fertilisation by honey-feeding birds such as the Tui 
(Prosthemadera) and Korimako (Axthornis). That the former 
bird regularly frequents the flowers I have repeatedly noticed ; 
and old and observant residents, who were well acquainted with 
the habits of the Korimako before its disappearance from the 
northern forests, all agree in stating that it was equally ready to 
take advantage of the luscious supply of honey offered by the 
plant. The exact mode of fertilisation hardly needs describing ; 
it is obvious that the bird, in thrusting its head between the 
styles of a recently-expanded raceme, must dust the feathers of 
the forehead and throat with pollen, and that when it visited 
flowers in a more advanced stage, the pollen would be rubbed 
off on the style, and probably smeared over the stigma. 
It is now well-established that, from causes that have hitherto 
eluded our research, undoubted advantages are possessed by 
cross-fertilised over self-fertilised plants; and an excellent 
argument in favour of this view may be inferred from the case 
of Kuightia. We find that the structure and arrangement of 
the parts of the flower are such that the style and stigma are 
actually embedded forsome time in a mass of pollen, so that no 
one can doubt that if self-fertilisation had been the preferable 
mode, it might have been obtained with certainty, and with a 
minimum expenditure of force. But instead of this we see a 
number of contrivances all pointing in the opposite direction. 
The ripening of the stigma is delayed, and its size reduced, in 
order that there may be no risk of contamination by pollen 
from the same flower; the summit of the style is enlarged to 
form a suitable stage on which the pollen may be presented to 
the visitors, to whom the task of transferring it from flower to 
flower is entrusted; the perianth segments are coiled up and 
removed from their path; and a suitable attraction is 
afforded in the abundant supply of nectar. Surely these 
contrivances would not be provided if some great advan- 
ee were not expected in return. -To my mind, cases 
similar to those of Awzghitza—and they are probably numerous 
enough—afford additional proof of the truth of Mr. Darwin’s 
well-known aphorism—*“ That ‘Nature tells us, in the most em- 
phatic manner, that she abhors perpetual self-fertilisation.” 
