New observations on the natural history of bees

by François Huber

From our own observations we found that the seminal fluid of drones coagulated on exposure to the air, and from several experiments had so little doubt on the subject, that whenever the female returned with the external marks of fecundation, we thought we recognised it in the whitish substance filling the sexual organs. It did not then occur to us to dissect the females to ascertain the fact more particularly: but this year, whether designing to neglect nothing, or to examine the distension of the female organs, we determined to dissect several. To our infinite surprise, what we had supposed the residue of the prolific fluid, actually proved the genital organs of the male, which separate from his body during copulation, and remain in the female.

We procured a number of queens according to Schirach's method for the purpose of dissection, and set them at liberty that they might seek the males. The first which did so, was seized the instant she returned, and without dissection spontaneously exhibited what we were so impatient to behold. Examining the under part of the belly, we saw the oval end of a white substance which distended the sexual organs. The belly was in constant motion, by alternate extension and contraction. Already had we prepared to sever the rings, and by dissection to ascertain the cause of these motions; when the queen curving her belly very much, and endeavouring to reach its extremity with her hind legs, seized the distending substance with her claws, and evidently made an effort to extract it. She at last succeeded, and it fell before us. We expected a shapeless mass of coagulated fluid; what therefore was our surprise to find it part of the same male that had rendered this queen a mother. At first we could not credit our eyes; but after examining it in every position, both with the naked eye, and a powerful magnifier, we distinctly recognised it to be that part which M. de Reaumur calls the lenticular body, or the lentil, in the following description.[O]

'Opening a drone there appears a portion formed by the assemblage of several parts, often whiter than milk. This on investigation is found to be principally composed of four oblong pieces. The two largest are attached to a kind of twisted cord, fig. 4. r, called by Swammerdam the root of the penis; and he has denominated seminal vessels, s. s. two long bodies that we are about to consider. Other two bodies oblong like the preceding, but shorter and not half the diameter, he calls the vasa deferentia, d. d. Each communicates with one of the seminal vessels near, g. g. where they unite to the twisted cord, r. From the other extremity proceeds a very delicate vessel, which, after several involutions, terminates in a body, t. a little larger, but difficult to disengage from the surrounding tracheæ. Swammerdam considers these two bodies, t. t. the testicles. Thus there are two parts of considerable size, communicating with other two still thicker and longer. These four bodies are of a cellular texture, and full of a milky fluid, which may be squeezed out. This long twisted cord, r, to which the largest of the seminal vessels is connected, this cord, I say, is doubtless the channel by which the milky fluid issues. After several plications, it terminates in a kind of bladder or fleshy sac, i. i. In different males this part is of various length and flatness. By calling it the lenticular body, or the lentil, it receives a name descriptive of the figure it presents in all males whose internal parts have acquired consistency in spirit of wine. The body, l. i. is therefore a lentil, a little thickened, of which one half, or nearly so, of the [circumference] is edged along the outline by two chesnut coloured scaly plates, e. i. A small white cord, the real edge of the lentil, is visible, and separates them. This lentil is a little oblong, and, for convenience, we shall ascribe two extremities to it, the anterior and posterior. The anterior, l, next the head, is where the canal, r, dividing the seminal vessels is inserted, and the opposite part; i. next the anus, the posterior. The two scaly plates, e. i. e. i, proceed from the vicinity of this last part, whence each enlarges to cover part of the lentil. Under the broadest part of each plate, there is a division formed by two soft points of unequal length; the largest of which is on the circumference of the lentil. Besides these two scaly plates, there are two others, n. n. of the same colour, narrower, and fully one half shorter, each of which is situated very near the preceding, and originates close to the origin of that it accompanies, namely, at the posterior part of the lentil. The rest of the lentil is white and membranaceous. From behind proceeds a tube, k. a canal also white and membranaceous, but it is difficult to judge of its diameter, for the membranes, of which it consists, are evidently in folds. To one side of this pipe is attached a fleshy part, p. somewhat pallet shaped, one side is concave, and the edges plaited; the other side is convex. In certain places the plaits rise and project from the rest of the outline, and form a kind of rays; the pallet appears prettily figured. Though lying with the concave side applied to the lentil, it is not fixed to it. Swammerdam seems to consider this pallet as the characteristic part of the male.

Figure 4

'Though the parts we have described are the most conspicuous in the male, they are neither those which protrude first, nor when protruded are the most remarkable. On viewing from the opposite edge of the lentil, forming the division of the two great scaly plates, a sac or canal, k. proceeding from the posterior part of the lentil, there is distinctly visible the body u, which we call the arc; where there are five transverse hairy bands of a yellow colour, while the rest is white. This arc seems out of the membranaceous canal because it is covered only by a very transparent membrane. One end almost reaches the lenticular body, and the other terminates where the membranaceous canal joins the folded yellow membranes, m. which form a species of sac, that is applied to the sides of the aperture, adapted for the genital organs passing through. These reddish membranes are those that appear first on pressure, and form this elongated portion, at whose end is a kind of hairy mask. Finally, with the sac formed by the reddish membranes, there are connected two appendages, c. c. of reddish yellow, and red at the end, s. These are what appear externally like horns.[P]'

The lenticular substance, l. i. provided with each scaly lamina, are the only parts of those described by M. de Reaumur, that we have found engaged in the organs of our queens. The canal, r, by Swammerdam denominated the root of the penis, breaks in copulation; and we have seen its fragments at the place where it unites to the end of the lentil, l. towards the anterior extremity; but we have found no traces of the canal, k, formed of involuted membranes, which in the body of the male proceeds from the posterior end of the lentil, l. i. nor of the plaited pallet, p. adhering to this canal, called by Swammerdam the penis from its resemblance to that of other animals, though he is not of opinion that this point, which is not perforated, can perform the functions of a real penis, and hold the principal part in generation. The canal, k, therefore, and all appertaining to it, must break at i, quite close to the posterior part of the lentil, since we found no remains of the lenticular bodies left by the fecundating males, in the body of our females. The canal, r, which Swammerdam calls the root of the penis, with greater reason than he was himself aware, is not extended in the body of the male as represented by the figure here engraved, but this long twilled canal consists of several involutions, from the seminal vessels whence it proceeds, into the lenticular body where it terminates, and where it conveys the fluid. This canal therefore can extend during copulation, and allow the lenticular substance to protrude out of the body of the males.

It is evident this may be the case during copulation as is seen on opening a drone, for, by endeavouring to displace the lenticular body, the involutions of the cord disappear, and it extends much more than necessary for the lentil to protrude from the body; and if we attempt to separate it farther, the canal breaks at l. close to the lentil, and at the same place where it breaks in copulation.

By dissection two nerves are discovered, towards the origin of the canal, r. inserted into the seminal vessels and distribute in them, and towards the root of the penis many ramifications undoubtedly serving for the motion of these parts. Two small parts, perceptible near the nerves, are two ligaments for retaining the generative organs in their proper place, so that except the root of the penis, they cannot be drawn out without some exertion; it and the lenticular body however can protrude, and actually do so during copulation. A certain degree of pressure forces all these parts from the body of the male, but they spontaneously return, and appear reversed.