have not space here to enter on this subject. Nor does there seem to me
any great difficulty in a single insect (as in the case of a
queen-wasp) making hexagonal cells, if she work alternately on the
inside and outside of two or three cells commenced at the same time,
always standing at the proper relative distance from the parts of the
cells just begun, sweeping spheres or cylinders, and building up
intermediate planes. It is even conceivable that an insect might, by
fixing on a point at which to commence a cell, and then moving outside,
first to one point, and then to five other points, at the proper
relative distances from the central point and from each other, strike
the planes of intersection, and so make an isolated hexagon: but I am
not aware that any such case has been observed; nor would any good be
derived from a single hexagon being built, as in its construction more
materials would be required than for a cylinder.
As natural selection acts only by the accumulation of slight
modifications of structure or instinct, each profitable to the
individual under its conditions of life, it may reasonably be asked,
how a long and graduated succession of modified architectural
instincts, all tending towards the present perfect plan of
construction, could have profited the progenitors of the hive-bee? I
think the answer is not difficult: it is known that bees are often hard
pressed to get sufficient nectar; and I am informed by Mr. Tegetmeier
that it has been experimentally found that no less than from twelve to
fifteen pounds of dry sugar are consumed by a hive of bees for the
secretion of each pound of wax; so that a prodigious quantity of fluid
nectar must be collected and consumed by the bees in a hive for
the secretion of the wax necessary for the construction of their combs.
Moreover, many bees have to remain idle for many days during the
process of secretion. A large store of honey is indispensable to
support a large stock of bees during the winter; and the security of
the hive is known mainly to depend on a large number of bees being
supported. Hence the saving of wax by largely saving honey must be a
most important element of success in any family of bees. Of course the
success of any species of bee may be dependent on the number of its
parasites or other enemies, or on quite distinct causes, and so be
altogether independent of the quantity of honey which the bees could
collect. But let us suppose that this latter circumstance determined,
as it probably often does determine, the numbers of a humble-bee which
could exist in a country; and let us further suppose that the community
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