Fertilization of the Scarlet Runner. 257 
downwards and towards the base of the left wing. To a spec- 
tator looking into the flower, the way, if any, to the base of 
the petals and of the ovary is obviously down the left wing 
and past the mouth of the spiral tube; but there is hardly 
room, in the quiescent state of the flower, even for the pro- 
boscis of an insect between the base of the wing and the keel. 
On following the development of the flower in the bud, it 
appears that the peculiarity of the spiral coil of the keel, with 
its enclosed stamens and pistil, only appears at a late stage. 
In the earlier stage, though the anthers and the brush round 
the style are fully formed, the length of the style, filaments, 
and keel, and the form of the keel, are like those of other 
papilionaceous flowers. 
The filaments of the stamens, which are, except one, united 
and stiff at the base, are in the upper part very thin and flexi- 
ble, and follow the windings of the spiral keel. The anthers, 
which are small, lie in two rows entirely within the tube or 
hollow of the keel, a little within its mouth, and within and 
below the stigma. 
The pollen is not very abundant, and is not dry and dusty, 
but moist and sticky. 
The style is stout, strong, and very elastic; it is set firmly 
on the stiff upright ovary, so that its poimt of attachment to 
the ovary and base of the flower is at some distance from that 
of the attachment of the keel to the stiff claw of the wing. 
The stigma is at the extremity of the spiral coil, and on the 
lower or outer side, ¢.e. on the side next the wings; it is 
sticky, and is clothed with fine hairs. In the untouched flower 
it just protrudes out of the mouth of the tube of the keel, so 
that its tip is just visible on looking downwards into the flower. 
A little below it the style is clothed with stiffish hairs or bris- 
tles, which partly encircle the style like a circular brush, but 
which are considerably more in number on the upper or outer 
side of the coil than on the inner or under side. This brush 
is opposite to and in contact with the opening anthers. 
Under these circumstances it is not obvious at first sight 
how the flower is fertilized. As regards self-fertilization, the 
arrangement does not seem a happy one; for the stigma is 
outside and below the tube of the keel, whilst the anthers and 
pollen are shut up within it. 
The plants are frequented by, indeed they swarm with, bees. 
These are of various kinds, of which I do not know the names. 
But, so far as I could see, the smaller or hive-bees never suc- 
ceeded in getting what they wanted through the mouth of the 
flower. They occasionally lighted on the petals, and looked 
in, but invariably went round to the back of the flower, and 
