PHYSIOLOGY OF THE FLOWER. 123 
Raspberry, blackberry, strawberry, apple, and hawthorn all agree 
in the possession of numerous stamens and excretion of honey 
by the receptacle. In blackberry the stigmas are mature before 
the inner stamens, which turn outwards as they ripen. ‘The last 
three display well-marked proterogyny, and, except the straw- 
berry, are sweet-scented. 
Roses do not excrete nectar, but are visited for pollen. The 
styles and stigmas project in the centre, and form a landing- 
place, so that crossing must often be effected, although many 
stamens are mature at the same time. 
Gooseberry, red currant, and black currant possess small greenish 
flowers, with minute petals, and five stamens. Nectar is excreted, 
however, from the top of the inferior ovary, and the first is pro- 
terandrous and self-sterile. 
Snowdrop excretes honey in groves on the inner surfaces of the 
small petals, upon which green streaks serve as honey-guides. 
The pendulous flower is approached by flying insects from below, 
when they are sure first to touch the stigma, which is placed on 
the end of the simple style that projects beyond the six stamens. 
The anthers dehisce by pores at their pointed ends, so that pollen 
can readily fall out upon an approaching insect. 
Wallflower and stock do not present many remarkable features. 
The stamens are tetradynamous, and the shortness of two of 
them is partly due to the fact that they have to curve round two 
of the nectaries, which are here small rounded green projections 
of the receptacle between them and the’ovary. ‘Two other similar 
nectaries are also present, one outside either pair of long stamens. 
The long claws of the petals are held firmly by the calyx against 
the structures within, and an insect alighting upon the platform 
constituted by the spreading limbs is, if already dusted with 
pollen, pretty likely to deposit some on the stigma, and to carry 
off a fresh supply while probing down to the nectar. 
Fuchsia is attractively coloured, and abundant honey is excreted 
by the top of the inferior ovary. Pollination takes place as in 
snowdrop, but the stigma is protruded more, and the anthers 
dehisce by slits. In fuchsia and snowdrop there is no specialized 
arrangement for causing pollen to fall upon insects. 
Heath (not heather) provides for this in a rather elaborate 
way. ‘The flower is pendant, and the contracted mouth of the 
urceolate corolla (for the shape of which we shall now see a 
reason) is almost blocked up by the style and stamens. The 
former projects somewhat, ready (as in most pendulous flowers) 
to receive pollen from approaching insects. The stamens, eight 
in number, arise from a honey-excreting receptacle, and their 
anthers form a ring round the style. The pollen escapes from 
