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Show 170 MESSRS. SCHAFER AND WILLIAMS ON THE [Jan. 18, tinuous with that of the gullet, and resembling it in all respects. is harsh to the feel, and in this respect contrasts strongly with the soft mucous membrane of the second and third regions. It is unnecessary to enter into details of structure as regards this epithelium, since it resembles others of its class, the lowermost cells (c1) being rounded or somewhat columnar, the layers above these composed of polyhedral elements with dentated or ridged surfaces, and those above these again swollen and enlarged ; finally, most superficial of all are several strata of flattened scaly cells forming a horny layer (h) distinguished, both by its somewhat fibrous appearance in section and by its different reactions to staining fluids, from the Malpighian layer or layers upon which it rests. Here and there one or two lymphoid corpuscles are to be seen in between the deeper epithelium-cells. A few papillae of the mucous membrane project into the deeper parts of the epithelium ; but neither an inspection of sections that were made from different parts, nor a careful examination of the surface, could detect any racemose or tubular glands of any sort in the region covered by this epithelium. At the line of demarcation separating it from the glandular portion of the stomach, the surface of the mucous membrane undergoes an abrupt change, perceptible as easily by the unassisted eye and hand as with the aid of the microscope. The manner in which the change takes place is represented in the figure, but will be more readily understood after the structure of the succeeding portion of the stomach has been described. It is sufficient here to mention that all the layers of cells of which the stratified epithelium is composed cease abruptly, with the exception of the deepest layer; this, on the contrary, becomes directly continued into the simple layer of columnar epithelium which covers the whole of the glandular portion, and which sends prolongations into the mouths of the glands. The Mucous Membrane of the Second Region.-This region and the remaining one include the whole of the glandular portion of the organ. The mucous membrane is soft to the feel and of considerable thickness; and its surface is closely dotted with the orifices of the tubular glands (Plate IX. fig. 2), which are densely arranged and pass either vertically or somewhat obliquely through the whole thickness of the membrane (which may, indeed, be stated to be in a large measure composed of them) as far as the muscularis mucosae (m. mi), which, as in man, limits the mucous membrane and separates it from the submucous areolar tissue. Each gland-tube is bounded (or rather may be said to be formed) by a delicate basement membrane, appearing in section as a mere line outside the epithelium of the gland. The tubes are cylindrical for the greater part of their length, but are somewhat enlarged towards the orifice, and also usually swollen out at the bottom (b). The surface of the mucous membrane between the orifices of the tubular glands is, as usual, covered by a single layer of characteristic columnar epithelium-cells (c), with the attached ends tapering, apparently designed, like the bricks in an arch, to accommodate themselves to the rounded surface to which they are attached; and this epithelium is con- |