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Show 126 MR. W. E. HOYLE ON T H E [Mar. 5, Enoploteuthis. The medio-lateral teeth are shorter and less acute than in either of these forms. The Anterior Salivary Glands are present and lie in the form of two ramified glands packed away in the floor of the mouth. Their openings are situated one on either side of the median elevation which forms the floor of the mouth anterior to the radula. The Posterior Salivary Glands are in contact with the inferior surface of the oesophagus, and slightly overlap the cephalic cartiiage ; they form a pyriform mass, the pointed extremity being directed backwards. The entrance of the duct into the oesophagus was not made out. The Oesophagus (Plate XIII. fig. 4, oe) is very slightly fusiform just behind the central nervous sy*>tem ; but it cannot be said that a crop is formed unless the expansion were very much greater than in the examples examined. Another fusiform portion is seen just before it opens into the stomach. The Stomach (s) is simple and saccular, more elongated in the larger specimen than in the smaller. In one of the examples from the Narwhal's stomach there was a chitinous lining, which had become completely detached. It appeared to have formed a coating over the whole inner surface of the organ, and is much thinner at the posterior extremity than it is a little way behind the oesophageal opening. There were, however, no dentiform prominences such as I hope to describe elsewhere in an account of the genus Taonius. In the same instance it contained a quantity of fragments of Crustaceans, but not one of them was large enough to give any chance of specific determination. The Rectum (r) as usual leaves the stomach close to where the oesophagus enters it, and about the same point is the opening of the • caecum. It presents no noteworthy features. The Ceecum (c) lies upon the anterior part of the ventral aspect of the stomach, somewhat towards the right. It is coiled into a complete spiral and presents a striated appearance which seems to be due to a series of folds in its lining mucous membrane. The Digestive Gland (d.g., "liver" of various authors) is large and ovoid and has the usual relations. The structure usually known as "pancreas" (pan.) is situated in the angle between it and the csecum and oesophagus. VIII. Circulatory Organs. The Heart (Plate XIII. fig. 3,v) is broadly pyriform in shape, the anterior end being somewhat narrower than the posterior; it is directed as usual almost antero-posteriorly, the anterior end being turned a little towards the right. At two opposite points in its largest diameter the heart receives the branchial veins (br.v), which as usual pass along the anterior or free side of those organs. There are only two aortic apertures to the heart, which are situated at its anterior and posterior extremities (a.ao, p.ao) ; the former gives off the cephalic aorta, quite in the ordinary manner. As regards the vessel from |