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the regularity of the comb is preserved.* This, however, is not done at definite intervals ; for in one piece of comb two intercalated series were nine cells apart, in another, six, and in another, four.
Mr. Langstroth has given a good figure, illustrating the form of the mouths of some of the cells where the worker and drone cells come together.f
The presence of a fourth face in the base of the transitional cells is by no means constant, as asserted by several observers, for we have seen the change from worker to drone cells without the fourth face appearing in any of them.
In all the transitional cells of brood-comb cocoons are invariably found, showing that they have been occupied. It is obvious that some of these would be either too large for a worker or too small for a
* This figure was made from a piece of old brood-comb, in which the lip of the drone cells was very much thickened, and the mouths were almost circular. There is nothing abnormal in this, except at those points where the row of intercalated cells, as a and b, connect with the drone cells.
† Treatise on the Bee, p. 74 and Pl. XV.
drone. It would, therefore, be of considerable interest to know whether such cells are occupied by one or the other of these kinds of bees. The determination of this point is important on another account. Siebold has ascertained that drones do not require impregnation, while the workers as well as the queens do ; and as the act of impregnation is voluntary with the queen, she is supposed to have some guide to inform her whether a given egg is to become one or the other kind, for she never makes a mistake and impregnates an egg in a drone cell, or omits to impregnate one in a worker cell. Siebold, therefore, supposes that the queen is guided by the size of the mouth of the cell, and if the abdomen touches one kind, impregnation takes place, and if the other, not. The transitional cells being intermediate, would not by their size give her the usual indication.
Honey Cells. — When the stock of honey becomes greater than the ordinary brood cells will contain, the bees either enlarge these, or add to them other cells often of larger capacity, or construct a new comb, devoted entirely to the storing of honey. While the cells of this last are built unequivocally in accordance with the hexagonal type, they exhibit a range of variation from it which almost defies description. Of all who have written on the subject, Mr. Langstroth is the only one we have met with who seems to have particularly mentioned their irregularity, which he does in the following words: “Those [cells) in which the honey is stored vary greatly in depth, while in diameter they are of all sizes, from that of a worker to that of drone cells.” * We have found them even 2.10 inches in depth, or four times that of a worker cell; sometimes they are square or pentagonal; their alignment is rarely if ever exact, so that the presence of a fourth face is more common than with the other kinds. The basal pyramid changes constantly ; the cast of a piece of comb, containing over four hundred cells, showed but few in which there was not some irregularity obvious to the eye ; either the faces were unequal, or there was a fourth, and even a fifth face, or the pyramid was too high or too low, or suppressed, or the body of the cell was not equilateral, or its angles too large or too small. The normal angle which one side makes with its adjoining ones is 120°; the following measurements, taken from casts of average specimens, exhibit a degree of variation by no means unusual.
* On the Honey-Bee, p. 74. New York, 1859.
135.0 Average of the 24 angles, 1190.5 Smallest,
110°.0 The above measurements were made with an accurate goniometer; those of cells I. and II. by Professor Cooke, and of III. and IV. by the author, and each is the average of three; but, in nearly every case, there is an error of from one to three degrees, which is inseparable from the measurement of surfaces and angles which are not exact.
When honey cells are built on a curved dividing wall, the bees seem to make no attempt to correct the effect of the converging and diverging lines. In the brood-combs they usually make an attempt, at least, to keep the cavity of the cells of the usual shape; but in the honey. comb we have seen the mouths of the cell in one diameter expanded to double their usual size. The most of the irregularities seem to have no obvious cause, but all looks as if the bees, aware that close conformity to the type-form was unnecessary for the mere storing of honey, became careless in executing their work.'
The distribution of the wax in the sides and angles of the cells, as seen in the sections, appears to the naked eye quite regular; but, with the aid of a low power, is often quite the reverse. One can easily detect an inequality in the thickness of the walls, - two different walls of the same cell, or two parts of one and the same wall being not unfrequently the one double the thickness of the other. The excavation of the angles, though sometimes wonderfully exact, is frequently done in such a way that the apices of opposite angles do not correspond. This is equally true of all of the three kinds of cells. In the cells, and still better in the casts of them, one can easily observe the fact that the edges of the sides are never exactly planes, and that consequently the line of union of two adjoining sides is somewhat undulating.
The statements made in the foregoing pages tend to show that the
cell of the bee has not the strict.conformity to geometrical accuracy so often claimed for it, but, as the best observers have maintained, is liable to marked variations, chief among which the following may be mentioned.
1st. The diameters of worker cells may so vary, that ten of them may have an aggregate deviation from the normal quantity, equal to the diameter of a cell. The average variation is a little less than one half that amount, viz. nearly 0.10 inch, in the same number of cells.
2d. The width of the sides varies, and this generally involves a variation of the angles which adjoining sides make with each other, since the sides vary not only in length, but in direction.
3d. The variation in the diameters does not depend upon accidental distortion, but upon the manner in which the cell was built.
4th. The relative size of the rhombic faces of the pyramidal base is liable to frequent variation, and this where the cells are not transitional from one kind to another.
5th. When a fourth side exists in the basal pyramid, it may be in consequence of irregularity in the size of the cells, or of incorrect alignment of them on the two sides of the comb.
6th. Ordinarily, the error of alignment does not amount to more than one or two diameters of a cell. But occasionally the rows of cells on one side of the comb may deviate from their true direction with regard to those on the other, to the extent of 30°. In consequence of this deviation and the continual crossing of the rows on opposite sides, the pyramidal base is not made, and the cell is thereby shortened.
7th. When a piece of comb is strongly curved, or two portions form an angle with each other, there is no constant way in which the tendency to the distortion of the cells is met; consequently the cells found at the curves or angles have a variety of patterns.
8th. Deformed worker and drone cells are used for rearing the young.
All of these variations are found in the three different kinds of cells, but are much more frequent and marked in the honey than in either worker or drone cells. In view of the frequency of such, however near the bee may come to a typical cell in the construction of its comb, it may be reasonably doubted whether a type cell is ever made. Here, as is so often the case elsewhere in nature, the type-form is an ideal one, and, with this, real forms seldom or never coincide. Even in crystallography, where the forms are essentially geometrical, we are told that "natural crystals are always more or less distorted or imperfect,” and that “the science of crystallography could never have been developed from observation alone”; * i. e. without recourse to ideal conceptions. An assertion, like that of Lord Brougham, that there is in the cell of the bee “ perfect agreement” between theory and observation, in view of the analogies of nature, is far more likely to be wrong than right; and his assertion in the case before us is certainly wrong. Much error would have been avoided, if those who have discussed the structure of the bee's cell had adopted the plan followed by Mr. Darwin, and studied the habits of the cell-making insects comparatively, beginning with the cells of the humble-bee, following with those of the wasps and hornets, then with those of the Mexican bees (Melipona), and, finally, with those of the common hive-bee. In this way, while they would have found that there is a constant approach to the perfect form, they would at the same time have been prepared for the fact, that even in the cell of the hive-bee perfection is not reached. The isolated study of anything in natural history is a fruitful source of error.
Since bees give so much variety to the forms of their cells, and can adapt them to peculiar circumstances, some of which do not occur in nature, as, for example, in Huber's experiment with the glass surface, which last they so persistently avoided, and in view of the fact, too, that in meeting a given emergency they do not always adopt the same method, one is driven to the conclusion that the instinct of one and the same species either is not uniform in its action and is quite adaptive in its quality, or to admit, with Reaumer, that bees work with a certain degree of intelligence.
Five hundred and sixty-first Meeting.
January 31, 1866. — STATUTE MEETING. The PRESIDENT in the chair. .
The Corresponding Secretary read letters from Prof. Tayler Lewis, Mr. L. M. Rutherfurd, Dr. J. W. Draper, Mr. G. W. Hill, and M. Chasles, in acknowledgment of their election into the Academy.
The President read a letter from Mr. Richard Greenough, presenting to the Academy a bust of Sir Charles Lyell.
* Professor Cooke, Religion and Chemistry, p. 287.