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Darwin, Charles, 1809-1882

"On the Origin of Species By Means of Natural Selection, or, the Preservation of Favoured Races in the Struggle for Life"

Grant
whatever instincts you please, and it seems at first quite
inconceivable how they can make all the necessary angles and planes,
or even perceive when they are correctly made. But the difficulty is
not nearly so great as it at first appears: all this beautiful work
can be shown, I think, to follow from a few very simple instincts.
I was led to investigate this subject by Mr. Waterhouse, who has shown
that the form of the cell stands in close relation to the presence of
adjoining cells; and the following view may, perhaps, be considered
only as a modification of his theory. Let us look to the great
principle of gradation, and see whether Nature does not reveal to us
her method of work. At one end of a short series we have humble-bees,
which use their old cocoons to hold honey, sometimes adding to them
short tubes of wax, and likewise making separate and very irregular
rounded cells of wax. At the other end of the series we have the cells
of the hive-bee, placed in a double layer: each cell, as is well
known, is an hexagonal prism, with the basal edges of its six sides
bevelled so as to join on to a pyramid, formed of three rhombs. These
rhombs have certain angles, and the three which form the pyramidal
base of a single cell on one side of the comb, enter into the
composition of the bases of three adjoining cells on the opposite
side. In the series between the extreme perfection of the cells of the
hive-bee and the simplicity of those of the humble-bee, we have the
cells of the Mexican Melipona domestica, carefully described and
figured by Pierre Huber.


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