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The sltamen-tube soon breaks up into nine free filaments which are bent upwards so as to lie in the 
keel. The single free stamen (fig. 2) is uppermost and runs along the inner face of the corolla-tube. 
Ultimately, like the other nine stamens it bends so as to lie within the keel. 
The pistil is attached to the base (thalamus) of the flower and is surrounded by the common tube 
formed by the union of the corolla and stamens (fig. 2). The ovary is short aud usually contains two 
ovules (figs, and 6). The sty/e is long, filiform and curved. The stigma (figs. 2 and 6) is contained in 
the cavity of the keel beyond the anthers (fig. 2). 
Red clover is one of those plants which remain barren and cannot produce seed, unless visited 
and fertilized by insects. It is absolutely necessary that the pollen be conveyed to the stigma by insect 
guests, Darwin found that 100 heads of red clover produced no seed when covered by a net to prevent 
the visits of insects to the flowers. Another 100 heads growing by the side of the former to which 
insects had access produced about 2720 seeds. The observations of Darwin and Miiller shew that bees 
are the chief fertilisers of red clover. Miiller, for example, found that 19 species of bee and 26 other 
species, belonging to the orders Hymenoptera and Lepidoptera, visited and fertilized the flowers. The 
insects come to obtain honey and pollen, During the visit some of the pollen which has attached ilself 
to the body of the insect, becomes fixed upon the stigma, and thus fertilization is secured. The pollen 
which is effective, has in all probability been taken from some other flower, previously visited. Cross- 
fertilization is thus accomplished. There is, however, no experimental evidence to show that pollen 
from a flower cannot, when applied to its own stigma, fertilize it. 
The flower is specially adapted for fertilisation, The nectar which the insects seek is secreted 
at the base of the tube formed by the united corolla and stamens; it collects round the base of the 
ovary. There is an open passage to the honey beneath the standard and between the wings. The 
insect takes up its position on the flower, inserts its proboscis and extends if in order to reach the 
base of the tube and sip the honey. To reach the honey the proboscis must be nine or ten mm. 
long — the same length as the tube of the flower. When the insect is sipping the nectar, it is 
standing on the wings and keel. The weight of its body presses down these organs and the stigma 
and stamens come into contact with the under surface of the insect’s head. The stigma is now fertilized 
by pollen from the insect and at the same time pollen is removed from the flower and attached to the 
hairs on the insect’s body. When the weight is removed by the flight of the insect, the elasticity of 
the keel brings the parts back to their original position, and the sexual organs are again enclosed in 
the keel. The processes which lock the wings to the keel aid in bringing the parts back, 
Some insects bore a hole in the corolla immediately above the calyx, and in this way, even though 
their probosces be short (7 to 9 mm.), they can readily reach the honey, without effecting any fertilization. 
The hole made by such robbers may again be used by other insects visiting the flowers later on. 
The fruit (fig. 7) is a one-seeded pod, divided by a transverse joint into two chambers, an upper 
and a lower. The upper is a smooth, shining, thin-walled cap; the lower a small, thin-walled box, 
which readily tears and allows the seed to escape. The pod of clover does not open by two valves and 
in this respect it differs from the legume generally characteristic of leguminous plants. 
The seed (figs. 8 and 9) itself is suborbicular or oblong and somewhat flat. On one of its edges, 
the radicle of the embryo forms a distinct projection, near the apex of which is the hilum (fig. 9). 
The colour is reddish or mustard-yellow, sometimes yellow on the edges and red on the surfaces. 
Because of its wide and extensive cultivation, this clover has received very varied local names. 
In this country it is usually called red clover or cow-grass. 
Red clover has contributed even more to the progress of agriculture than the potato itself, and 
has had no ineonsiderable influence on European civilisation. Its cultivation has led to an increased 
production of stock as food for man, and in this way has fostered and advanced commerce, industry and 
science, Although indigenous to Europe, red clover has only been introduced to cultivation within 
comparatively recent times, 
Name. 
History. 
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