laying up
stores during spring. His store consists of acorns. He has not time to
fix them one by one, like the _Melanerpes_, and only thinks at first
of rapidly collecting a large quantity. But it is in deciding the
question as to where they are to be laid up that the _Colaptes_ shows
his remarkable intelligence. In the forests where he lives are to be
found aloes, yuccas, and agaves. When the agaves have flowered, the
flower-bearing stem, two or three metres in length, shrivels, but
remains standing for some time. Its peripheral portion is hardened by
the heat, while the sap in the interior almost entirely disappears. A
hollow cylinder with a well-sheltered cavity is thus formed, and the
_Colaptes_ proposes to utilise it as a storehouse. His acorns will
there be well protected against external influences and against the
birds whose beaks are too weak to pierce the agave. It is then a
question of filling the tube. The animal first pierces the wall
towards the base of the stalk; through this hole he introduces acorns
until he has filled the lower part of the cavity. This done, he makes
a new hole rather above the first, and fills the interval between the
two, continuing this process until he has arrived at the top of the
stalk and filled the whole interior. (Figs. 10 and 11.) The bird seems
at first to take unnecessary trouble by boring so many holes. He would
reach his end as well, it would seem, by making a single hole at the
top to fill his storehouse, and another at the bottom to empty it. But
we must not thus accuse him of lack of judgment. The interior of the
tube is just large enough for the passage of an acorn; but at certain
points the sap is not entirely absorbed, and there might easily be an
impediment which would leave a large part of the cavity empty. Hence
the necessity for a number of openings. When the sun has scorched up
plants, and provisions are rare, he turns to his barns of abundance.
Now and every time that he has need he can utilise the method that has
been employed by his cousin the _Melanerpes_. In order to feed on each
acorn without too much trouble, or allowing it to slip from his beak,
the bird places it in a vice. He hollows a hole in the trunk of a
tree, introduces the fruit there forcibly, and eats it at his
ease.[52]
[52] Henri de Saussure, "Observations sur les moeurs de
divers oiseaux du Mexique," _Arch. Sci. phys. et natur._,
1859, pp. 21-41.
[Illustration: FIG.
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