REPRODUCTION BY SEED 167 
flowers are small and inconspicuous, but the stigmas are 
large and feathery, and project beyond the flower. The 
anthers burst when the air is dry, and clouds of golden 
dust are shot from them. If they burst in wet weather, 
rain would wash the pollen upon the earth, and it would 
be wasted. In many wind-pollinated flowers the pistils 
ripen first, so that they may be ready to catch the first 
pollen that is wafted along their way. Among wind- 
pollinated plants are many of our lofty forest-trees— 
pines, oaks, beeches, poplars, elms, birches—bushes like 
the hazel, climbers like the hop, water-plants like Myrio- 
phyllum, weeds like stinging-nettles and plantains, and 
all the grasses, reeds, and sedges. Most of our catkinate 
trees (p. 180) are wind-pollinated, and they flower very 
early when the trees are bare of leaves. The presence of 
the leaves would obstruct the passage of the pollen to 
the flowers. The oak flowers after the leaves are out, but 
the position and form of the leaves are such that they 
interfere very little with the passage of the pollen through 
the tree. If foliage is present, the wind-pollinated flowers 
are raised well above the leaves—e.g., grasses. In the 
pine the pollen is provided with floats. 
There is little doubt that in the evolution of flowers 
wind-pollinated flowers preceded insect-pollinated flowers, 
the advance being made in the direction of economy of 
material and of increasing certainty of pollination. But 
of existing flowers, some that are wind-pollinated have 
always been so—e.g., conifers ; others have degenerated 
from insect-pollinated ancestors. The latter usually 
show signs of their degradation. The pollen may be still 
somewhat sticky—e.g., Poterium Sanguisorba ; remnants 
of attractive corollas may persist—e.g., Thalictrum minus ; 
and honey may even be secreted—e.g., Rumex, Poterium. 
3. Insects.—Flowers pollinated by insects are called 
““entomophilous”’ (Gr. entomon, insect). Unlike the 
wind, the movements of insects are directed by a definite 
purpose. They visit flowers, sometimes for shelter, 
occasionally as a suitable place to deposit their eggs, 
but generally in quest of food. The adaptations of 
flowers to insects and of insects to the flowers which they 
visit are very curious and wonderful. Beauty of form, 
colour, scent, and honey are all adaptations which have 
arisen among flowers for the attraction of insect-visitors. 
