Foxglove and Toadflax 257 
stiff hairs. A bee thrusting in his proboscis low 
down, would be repulsed by the spiny filament- 
processes, and compelled to try higher up, where he 
first touches the stigma and pollinates it, then push- 
ing between the anthers disarranges them, and 
brings a shower of pollen in a narrow line above his 
proboscis. | 
There are two races or sub-species of the Yellow 
Rattle, growing side by side, and distinguished as 
major and minor. That which we have described is 
major, the normal form, and this is so freely visited 
by insects and so invariably gets cross-fertilised that 
it has lost the power of self-fertilisation—the stigma 
growing out beyond the anthers where their pollen 
cannot possibly fall upon it. But the corolla of 
minor scarcely exceeds the calyx in length, and it 
consequently loses so much of its attractiveness that 
insect-visitors are comparatively rare, in spite of the 
fact that the shortness of the tube renders the honey 
accessible to short-tongued bees as well as to those 
with long proboscides. This small flower evidently 
failing to become more attractive, gets over the 
difficulty with a little ingenuity: the style increases 
in length, and curls inward so that the stigma comes 
under the anthers, which discharge their pollen upon 
it, and so self-fertilisation is effected. Here again, in 
two forms of a plant with similar mechanism, and 
growing in the same places under like conditions, 
we have a striking object-lesson of the advantages 
derived from a slightly increased size in securing 
cross-fertilisation. This conspicuousness is increased 
by the tip of the upper lip in mayor being blue, whilst 
in mumor it is white. When the flower hangs down 
