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Show 1887.] MR. F. E. BEDDARD ON MYRMECOBIUS. 529 of the excretory duct, which is so generally met with in sweat-glands. The lumen of the duct is extremely fine. In many cases the duct, formed by the coalescence of the ductules of the several tubules, instead of passing directly on to the exterior of the body, was seen to open at the base of a sudoriparous follicle; in this case the duct appeared tu maintain its independence, and to pass through the follicle onto the exterior, not to become continuous with one or more of the glandules in the follicles. (2) Sebaceous glands. In the description of the naked-eye characters of the glandular patch, it has been stated that it is bare without any hairs ; a microscopical study shows, however, that there are a few hairs situated chiefly at the periphery ; these are generally furnished with a pair of sebaceous glands presenting the ordinary characters. (3) Sudoriparous follicles. The glandular follicles opening on to the exterior by the conspicuous orifices with which the patch is covered appear to be of the nature of sweat-glands ; these follicles are filled with a mass of tubules which pass straight from their point of attachment to the external aperture of the follicle ; these tubules are club-shaped, the lower extremity being somewhat swollen. This part of the gland is composed of cells which agree exactly in their characters with the cells of sebaceous glands, and, like them, are hardly affected by borax carmine; very frequently tbe lower extremity of the gland appeared to be bifid. The individual glands are separated from each other by cells which stain deeply with borax carmine, and are in every way similar to the cells of the epidermis ; there is a complete layer of these cells lining the follicle, and the extremities of the glands have the appearance of being imbedded in them. The proximal part of each gland consists of a long straight tube surrounded by layers of unstriped muscular fibres and lined with epithelium. Although in many particulars these glands resemble sebaceous glands, the presence of muscular fibres is, in tbe present state of our knowledge, decisive in favour of referring them to the sudoriparous series. It is clear, however, from the above description and figures that these glands differ in many points from the typical sweat-glands. So far the glandular structures are confined to the integument ; beneath the layer of loose connective tissue which underlies the dermis is (4) A large compound tubular gland, quite half an inch in diameter; this gland recalls in its general aspect the arm-gland of Hapalemur ; its structure is like that of the sweat-glands, and it is divided into unequally-sized lobules by partitions of connective tissue. I have been quite unable, however, up to the present to detect the external orifice or orifices of this gland. The above-mentioned structures form altogether a complicated glandular mass which is unparallelled amoug mammals. Special tegu-mentary glands produced by a local hypertrophy of sebaceous or sweat- 'lands are extremely widely spread among the Mammalia ; but I am not acquainted with any integumental glandular structure which has so complex a character as the sternal gland of Myrmecobius. What |
