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An illustration of the gradual appearance of the Sylvian fissure with the hippocampal formation, is attempted below:

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The last cut represents the Sylvian fissure formed as in man, with the accompanying fascicular distortions:

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The growth of the frontal lobe in proportion to the intelligence of the primate individual, augments this creation of temporal. Many of the longitudinal sulci of the quadrumana fold over and under with this advancement of the occipital into temporal, and the parieto-occipital fissure on the median face of the cerebral hemisphere is doubtless created directly by this bend, and the calcarine may also owe its origin to this change. A variety of causes combine, however, in fissure formation, aside from those mentioned.

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THE BEE'S TONGUE, AND GLANDS CONNECTED WITH IT.

BY JUSTIN SPAULDING.

THE 'HE present paper is the outcome of an interest in the subject

awakened by an article, by Mr. J. D. Hyatt, on the sting of the honey bee, in the American Quarterly Microscopical Journal for October, 1878, followed by one on the structure of the tongue by the same, July, 1879. Both bear impress of careful and painstaking interpretation of facts, and a genius in manipulation that is truly marvelous. Mr. Chamber's article, prior to Mr. Hyatt's

and which he criticises, I have not seen, and am indebted to Mr. Hyatt for what knowledge I possess of it. His article on the bee's sting, reading so like a fairy tale, incited me to attempt to demonstrate for myself if it was indeed the marvelous little structure described, and I can add my testimony (which he certainly does not need) to the literal accuracy of description, drawing and, as I believe, of his interpretation of the bee's manner of working it. That the bee can sting, every boy of ordinary enterprise can testify from personal experience, but Mr. Hyatt has spread before us the whole villainous apparatus, and initiates us into every motion, so that if one could be philosophical (under the circumstances a hard thing to do, even deacons are said to forget themselves and indulge in a mild form of profanity) the various stages of agony could be explained in learned terms, up to and including the final jab of the two blades, that leaves the victim to retire, swell up, and figure out his net gain from the operation. But to pass to the other end of the bee, which directly concerns us in this article.

My own observation, so far as the ligula is concerned, agrees with Prof. Cook's (see NATURALIST, April, 1880), and I think he has given the true solution when he says it consists of a sheath slit below, within which is the grooved rod, and projecting from the edges of the latter to the edges of the sheath, is a thin membrane, forming, as will be easily understood, when the rod is extended or thrown down, an enclosed sack, open only at the top. For the benefit of those who may still doubt as to this structure, I have drawn, under the camera, a very fine cross section of the ligula, kindly loaned me for the purpose by my friend, Mr. David Folsom. He has succeeded in cutting it from a specimen with the rod thrown out of the sheath (see Fig. 5).

In going over the work of Mr. Hyatt, while examining a mounted specimen of mouth parts, my friend, Mr. F. B. Doten, pointed out, in the mentum, a small spiral tube that gave me a clue, which followed up, has resulted, as I believe, in a slight addition to our knowledge of the parts. I am unable to find any mention of the glandular structure, a description of which follows. The drawing, No. 1, showing the head, is somewhat diagramatic; structures that might confuse being neglected. The specimen here represented was taken while fresh, pressed flat, dried under pressure, bleached in turpentine and mounted in damar.

It shows the structure as represented, from the tip of the ligula

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FIG. 1.-Diagramatic. a, point where spiral tube enlarges; m, mentum; sm, sub-mentum; /, mandibles; b, opening into mouth; c, entrance of ducts from head; d, junction of ducts from thorax; g, glands in thorax.

to the opening in the mouth at b. Beyond that I had to resort to dissection, not extremely difficult with a sharp scalpel, a steady hand and patience. It is best performed on alcoholic specimens, and the magnified drawing, under camera, of the gland from the thorax (see Fig. 3), it will be understood is somewhat shrunken on that account.

Running the scalpel from the base of one mandible back across close to the neck and forward to the other mandible, turn forward and pin, remove the brain and salivary glands; cut the œsophagus as far forward as possible, turn it back, and if all has been done carefully, one sees coming from the thorax the spiral ducts of two glands, which will be found, on following back, lying one on each

FIG. 2.-Fragment of glands of head much magnified.

side of the œsophagus, in the space between the muscles of the wings. I have given one of these, Fig. 3, magnified thirty-five diameters, as drawn under the camera. It could be but little more than outlined, as it was a dense mass of coiled and twisted glands, the true structure of which is shown (Fig. 4) still more magnified.

At the base, the duct enlarges, as is seen, into quite a reservoir. The ducts unite within the neck, or just as they enter the head, and following the floor of the latter, are joined by a pair coming in right and left (Fig. 1, c). Following up one of these side glands, we find it dividing into three main branches, ultimately terminating in glands, the structure of which is shown in Fig. 2 much enlarged. It will be seen that the glands from the thorax bear a striking resemblance to the Malpighian tubules of insects,

while those from the head are larger, different in shape, and composed of much smaller cells. Keeping to the floor of the head, the main duct passes on to the sub-mentum. Here on joining the spiral tube coming from the ligula, it passes by an opening common to both into the mouth at b, Fig. 1. Below the opening the spiral tube dips into the mentum, and is imbedded in its muscles.

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FIG. 3.-One of the glands of the thorax, magnified thirty diameters.

At a (Fig. 1) it seems to terminate, judging from a side view, but a series of cross sections shows it to gradually widen from a (Fig. 1) to near the base of the ligula, where it terminates in a chamber that leads above into the sack, and below by a valvular opening into the groove in the rod. This trumpet-shaped part from (a) to the chamber at the base of the ligula, is collapsed, the upper half of the tube being pressed down into the lower half.

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