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Show 168 MESSRS. SCHAFER AND WILLIAMS ON THE [Jan. 18, pyloric fundus. This patch is distinguishable to the unaided eye chiefly by its greater thickness, smoother surface, and by a slight furrowed line which partly encloses it. It shows under the microscope glands differing in character from those of the surrounding region, and is therefore here described as a third region of the mucous membrane. But this third region is not entirely confined to the circular patch ; for a narrow tract of mucous membrane (n) containing similar glands extends from the upper limit of the patch on either side to meet its fellow above at the lesser curvature, thus completing an irregular zone around this part of the stomach. In Macropus giganteus the epithelium of the first region (Diagram 2, A ) has a much more limited distribution than in Dorcopsis. The tract which it covers is widest in the neighbourhood of the gullet, whence it passes over the front and back of the stomach. Even here it does not extend as far down as the greater curvature; so that the two parts do not meet below. Moreover the left end of the stomach, which terminates in a pouch-like projection (p), is not lined by this epithelium, although a second smaller pouch (p), directed upwards and situated nearer the gullet than the first one, receives a lining from it. Both these pouch-like projections are Diagram 2. Stomach of Macropus giganteus. present also in Dorcopsis luctuosa ; but they are both lined with hard epithelium like that of the rest of the cardiac fundus in this animal. Anteriorly the hard epithelium gradually narrows in Macropus giganteus until it becomes reduced to a mere strip along the lesser curvature, and eventually ceases altogether about halfway between the two extremities of the stomach. The ridges of mucous membrane which extend towards the right from either side of the cardiac |