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ANNIVERSARY ADDRESS 
form and colour to the stones among which it grows, escapes the 
notice of cattle and wild herbivorous animals. Kerner draws 
attention to the colour of some silenes which open at night and 
display an inner surface of white, while when closed “ they are 
curled up and expose their under side to view, which is of an in¬ 
conspicuous colour.” 
An interesting case of “ hiding” is seen in the hardy cyclamens. 
When the flower falls off in January, the top of the stalk bends so 
that the seed-capsule is held in a horizontal position. The stalk 
now slowly coils itself irregularly round the capsule, and, bending 
with the increased weight at its extremity, lowers the capsule 
gradually to the earth, where it is protected not only by the leaves 
of the plant but also by the coil of the decayed stalk. During the 
next few months the alternate contraction and expansion of the 
soil due to the different degrees of moisture and temperature, causes 
the capsule to become wholly or partly buried, and the safety of 
the seeds, which do not ripen until June, is secured. In gardens, 
the capsules are generally completely covered about the middle of 
February by the manure which is usually placed in late autumn on 
the ground. It is worth noting that the foliage of these plants 
is dense and falls only in the spring, so that if the stalks dropped 
with the capsules they would afford their capsules no such pro¬ 
tection as they receive from the canopy of leaves and the soil. 
In hot-house varieties I have not seen this process, but I am in¬ 
formed that it does not there occur with them, and, if this be the 
case, it appears to me that they fail from want of vitality. A 
modification of this plan is seen in other plants. The flowers of 
Trifolium sulterraneum are drawn underneath the ground, and 
Arachis hypogea and Voandzeia sulterranea only produce subterranean 
seed-pods. Correae de Mello* has described his experiments on 
these two Leguminosce, and states that when the ovaries were pre¬ 
vented from penetrating into the ground either by the interposition 
of a resisting body or by raising the branch as in the case of Arachis 
hypogea , they did not enlarge, and remained in the same state 
until the plant perished. The branches of Voandzeia sulterranea 
spread along the ground, and its flowers are just above the surface. 
Should, however, the ovaries of these two plants not penetrate the 
soil, the peduncle dries up and no pod is formed. 
In the case of Vallisneria spiralis we find that the flower of the 
female plant is borne on a long spirally-twisted stalk which uncoils 
according to the depth of the water, so that the flower may float 
on the surface. After fertilisation has taken place, the stalk 
* ‘ Journal of the Linnean Society,’ vol. xi, p. 254. 
