rats, and from those acorn-eating birds whose bills are not strong or sharp enough to cut through their tough enclosures? M. Sumichrast, who afterwards enjoyed unusual opportunities for observing the habits of these Woodpeckers in the State of Vera Cruz, states that they dwell exclusively in oak woods, and that near Potrero, as well as in the alpine regions, trunks of oak-trees are found pierced with small holes in circular lines around their circumference. Into each of these holes these birds drive the acorns by repeated blows of their beaks, so as to fix them firmly. At other times they make their collection of acorns in openings between the raised bark of dry trees and the trunks. This writer states that he has sought in vain to explain such performances satisfactorily. The localities in which these birds reside, in Mexico, teem at all seasons with insects; and it seems absurd, therefore, to suppose that they can be in quest of the small, almost microscopic, larvæ contained in the acorns.
Dr. C. T. Jackson sought to account for these interesting performances on the ingenious hypothesis that the acorns thus stored are always infested with larvæ, and never sound ones; that they are driven into the tree cup-end foremost, so as to securely imprison the maggot and prevent its escape, and thus enable the Woodpecker to devour it at its leisure. This would argue a wonderful degree of intelligence and forethought, on the part of the Woodpecker, and more than it is entitled to; for the facts do not sustain this hypothesis. The acorns are not put into the tree with the cup-end in, but invariably the reverse, so far as we have noticed; and the acorns, so far from being wormy, are, in nine cases out of ten, sound ones. Besides, this theory affords no explanation of the large collections of loose acorns made by these birds in hollow trees, or in the stalks of the maguay plants. Nor can we understand why, if so intelligent, they make so little use of these acorns, as seems to be the almost universal testimony of California naturalists. And, as still further demonstrating the incorrectness of this hypothesis, we have recently been informed by Dr. Canfield of Monterey, Cal., that occasionally these Woodpeckers, following an instinct so blind that they do not distinguish between an acorn and a pebble, are known to fill up the holes they have drilled with so much labor, not only with acorns, but occasionally with stones. In time the bark and the wood grow over these, and after a few years they are left a long way from the surface. These trees are usually the sugar-pine of California, a wood much used for lumber. Occasionally one of these trees is cut, the log taken to mill without its being known that it is thus charged with rounded pieces of flint or agate, and the saws that come in contact with them are broken.
Without venturing to present an explanation of facts that have appeared so contradictory and unsatisfactory to other naturalists, such as we can claim to be either comprehensive or entirely satisfactory, we cannot discredit the positive averments of such observers as Saussure and Salvin. We believe that these Woodpeckers do eat the acorns, when they can do no better.
And when we are confronted with the fact, which we do not feel at liberty to altogether disregard, that in very large regions this bird seems to labor in vain, and makes no use of the treasures it has thus heaped together, we can only attempt an explanation. This Woodpecker is found over an immense area. It everywhere has the same instinctive promptings to provide, not “for a rainy day,” but for the exact opposite,—for a long interval during which no rain falls, for nearly two hundred days at a time, in all the low and hot lands of Mexico and Central America. There these accumulations become a necessity, there we are informed they do eat the acorns, and, more than this, many other birds and beasts derive the means of self-preservation in times of famine from the provident labors of this bird. That in Oregon, in California, and in the mountains of Mexico and elsewhere, where better and more natural food offers throughout the year, it is rarely known to eat the acorns it has thus labored to save, only seems to prove that it acts under the influences of an undiscriminating instinct that prompts it to gather in its stores whether it needs them or not.
It may be, too, that writers have too hastily inferred that these birds never eat the acorns, because they have been unable to obtain complete evidence of the fact. We have recently received from C. W. Plass, Esq., some interesting facts, which, if they do not prove that these birds in the winter visit their stores and eat their acorns, render it highly probable. Mr. Plass resides near Napa City, Cal., near which city, and on the edge of the pine forests, he has recently constructed a house. The gable-ends of this dwelling the California Woodpeckers have found a very convenient storehouse for their acorns, and Mr. Plass has very considerately permitted them to do so unmolested. The window in the gable slides up upon pullies its whole length, to admit of a passage to the upper verandah, and the open space in the wall admits of the nuts falling down into the upper hall, and this frequently happens when the birds attempt to extricate them from the outside. Nearly all these nuts are found to be sound, and contain no worm, while those that fall outside are empty shells. Empty shells have also been noticed by Mr. Plass under the trees, indicating that the acorns have been eaten.
The Smithsonian Institution has received specimens of the American race of this Woodpecker, collected at Belize by Dr. Berendt, and accompanied by illustrations of their work in the way of implantation of acorns in the bark of trees.
The eggs of this Woodpecker, obtained by Mr. Emanuel Samuels near Petaluma, Cal., and now in the collection of the Boston Society of Natural History, are undistinguishable from the eggs of other Woodpeckers in form or color, except that they are somewhat oblong, and measure 1.12 inches in length by .90 of an inch in breadth.
Melanerpes formicivorus, var. angustifrons, Baird.
THE NARROW-FRONTED WOODPECKER.
Melanerpes formicivorus, var. angustifrons, Baird, Cooper, Orn. Cal. 1, 1870, 405.