The Solens are singular from the power they possess of burying
themselves in the sands on the coast, sometimes even to the depth of a
couple of feet. The foot of the Solen, by means of which it is able to
penetrate the sand, is equal to one-half of the length of the shell.
Their movements are confined to rising to the surface of the sand in
which they have formed their hole, and in again sinking to the bottom.
This movement is, no doubt, produced by the action of the foot, which
forms itself into a sharp point in its descent, and when it remounts is
enlarged as much as possible, to form a resting-point, for the purpose
of raising the shell to the surface. It is not supposed that the animal
ever entirely leaves its hole of its own accord, although it may
possess the power; but it is certain, according to the observations of
Réaumur, that if forcibly removed it can re-enter it. The hole it forms
for its retreat is always perpendicular.
[Illustration: _Tellina. Solen vagina. Pandora rostrata._]
One of these creatures, being taken out of its retreat, was laid on
the sand; it first extended its foot in the form of a wedge, or rather
cone, and, applying it to the surface of the sand, slightly raised the
farthest end of its shell; at the next effort the projecting part of
the foot was buried in the sand, and the shell became more elevated;
after two or three more attempts the hole had attained a perpendicular
direction, and the shell was partly buried in it; the shell then began
to descend, and that with considerable quickness.
The Solens are used sometimes, but rarely, for food; but in places
where they abound, they are sought after as bait for fishes: the method
of taking them is very singular. Having discovered the place of retreat
of the creature, by observing the hole in the sand which leads to its
chamber, the fisherman throws into its entrance a small quantity of
salt. Although an inhabitant of salt water, the pure salt produces so
irritating an effect on the extremity of its body, that it quickly
mounts to the surface; the fisherman, waiting for its appearance,
snatches hastily at it, and if he succeeds in seizing it firmly, makes
good his capture; but if not sufficiently active, and the animal
escapes, the application of fresh salt produces no further effect;
either it is not sensible to the additional infusion of salt, or, which
is most likely, the instinct of self-preservation causes it to put up
with the inconvenience rather than be taken. In this case, no other
means are left of securing it, than using an iron instrument to dig it
out with. The number of species is upwards of twenty.