The outer or longitudinal muscle layer, _lm_, is comparatively little developed and consists of small rather scattered bundles of muscles with a correspondingly large amount of connective tissue. This connective tissue passes insensibly into that of the surrounding serosa, _s_, a loose, vascular layer of varying thickness and density, shown very thick in Figure 45, but often much thinner. So far as could be determined, the mucous membrane has the same structure in both anterior and middle regions of the stomach. That of the pyloric or small region, although fixed, stained, et cetera, just as carefully as the rest, did not show cell details sufficiently well to draw; the ducts of the glands in this region are fairly distinct but the deeper parts of the glands have the appearance of series of alveoli or large adipose cells. What the significance of this condition may be the writer is not able to say, but since the structure of this region of the gastric mucous membrane is not clear no attempt will be made to describe its appearance under higher magnification than was employed in the figure above. However, as will be noted below, there is probably no great difference between the pyloric mucosa and that of the other regions of the stomach. [Illustration: FIG. 46. The glands of the middle or fundic region of the stomach of the hibernating animal, under high magnification; _A_, through duct; _B_, through body of gland; _C_, through fundus of gland.] Figure 46 shows portions of typical glands from the mucosa of the middle region of the stomach, the posterior border of the large stomach cavity; _A_ is a longitudinal section through two ducts where they open to the surface; _B_ is a similar section through the body of a gland below the region of the duct; _C_ is a transsection through the bottom or fundus of a gland; all are drawn with a camera under the same magnification. As is seen in Figure 45, under low magnification, the duct is about one third of the entire length of the gland. The lumen of the duct is fairly wide, that of the body of the gland is reduced to a mere slit, while that of the fundus is quite wide. One, two, or possibly more, glands may open to the surface through one duct, as is shown in Figure 46. There is nothing peculiar about the epithelium of these glands. Near the opening of the duct the cells are of a typical columnar character with finely granular cytoplasm, each with a nucleus at its basal end. In the deeper parts of the duct the cells become shorter until in the body of the gland (Fig. 46, _B_) they are cuboidal in outline. The bodies of the glands are so closely packed together that it is difficult to pick out an individual tube that will show details clearly enough to draw with a camera lucida. So far as could be observed all of the cells of this region of the gland are alike.