126 THE FLOWERING PLANT. 
nectar is excreted deep down between sepal and style, and the 
bee, in backing out, rubs its head against the anther. The little 
shelf is not stigmatic below, and is simply lifted up out of harm’s 
way for a moment. 
The most daring way by which self-pollination is avoided by 
regular flowers is where the style actually assists in the distribu- 
tion of pollen. This is seen in harebell (and Canterbury bell) and 
many Composites. In the former case the anthers shed their 
pollen before the flower opens, and a great deal of it adheres to 
the hairy outer surface of the style. Later on, the three (or 
more) lobes in which the style terminates expand and display 
their stigmatic inner surfaces. 
The regular disk florets of a daisy or sunflower will illustrate 
the method in many Composites, and show the meaning of 
syantherous stamens. ‘Take, for example, a half-blown example 
of the larger form. The youngest inner florets are still shut. 
Outside these come a large number in which the brown anther- 
rings are very conspicuous. Dehiscence is znternal, and by 
looking at older and older florets (7.e., passing gradually to the 
outside), you will find that first a small heap of pollen is seen on 
the top of the anther, and then the elongating style gradually 
emerges. It is provided with a little brush of hairs at its end, 
and, in fact, sweeps the pollen clean out of the tube, afterwards 
spreading into two lobes, stigmatic, as will be anticipated, inter- 
nally. ‘The most external disk-florets will be found already 
pollinated, with stigma and stamens withered. Aggregation 
not only renders Composites conspicuous, but also makes them 
favourites with insects, since a great deal of nectar is attainable 
in a small area. Their visitors alight in what must relatively 
be a perfect thicket of anthers and stigmas in various stages of 
maturity. Cross-pollination cannot but be extremely frequent. 
Il. Irregular Flowers.—Larkspur contrasts strongly with the 
closely related buttercup. Bees alight on the large petaloid 
sepals (cf p. 85), and to reach the nectar contained in the two 
spurred petals, must pass their tongues through a small opening 
between the upper leaves of the perianth. Now the principle 
alluded to on p, 121 comes into play. The stamens mature first, 
and successively raise themselves into this opening, retiring 
afterwards. Lastly, the stigmas are lifted up into the same 
position. 
Indian-cress (so-called garden nasturtium) works on the same 
lines, but the nectar is here contained in the spur of the gamo- 
sepalous calyx. 
Papilionaceous flowers present many interesting modifications. 
In all of them the wings (cf. p. 88) serve as a landing-stage, 
