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Show 1867.] DR. H. BURMEISTER ON PONTOPORIA BLAINVILLII. 487 tirely attached to the cartilaginous carpus. It has only a short cartilaginous tip on the other end. The four following fingers have all a large cartilaginous articulated axis, which includes in the first or second articulation an ossified nucleus. The second finger has six, the third five, the fourth three, and the fifth two articulations, the last of all being only a thin conical prolongation. A similar cartilaginous conical piece is situated between the third and fourth fingers, in the substance of the fin near the exterior margin. Of the posterior members I have found only the usual small pelvic bones, situated on each side of the anal cleft. From the fortunate circumstance that some parts of the viscera were preserved in a dry state in the interior of the body, I had the good fortune to be able to examine the larynx with the trachea, and the oesophagus with the stomach. I found in one of these parts a curious peculiarity, which I will explain by the aid of the annexed figure, of two-thirds the natural size. The larynx (fig. 2, p. 488), which has the usual prolonged conical form above (a), is very large below, the thyroid cartilage (b) being extended on each side to a distant arch, which is united behind by articulation with the cricoid cartilage (c). Beyond this cartilage the trachea begins as a large channel or tube, which is surrounded by three or four spiral cartilaginous rings of the construction usual in all Cetaceans (d). Then it divides into three branches of unequal size-two superior smaller, and one inferior wider. Of the two superior the left (e) is somewhat wider than the right (f), but of the same construction as the commencing trunk and the central branch of the trachea, and perhaps also of the same length; but both branches were cut away in the specimen examined, the left being ly inch long and the right only 1 inch. The longer, middle branch (g) was preserved to the end, and had a length of 3 inches, then it divided into two branches, of which the left (h) is also somewhat wider than the right (k). There is no doubt that these branches represent the two bronchi of the other air-respiring vertebrata; but it is curious that the difference in size is much greater than is usually the case. I could follow both bronchi to their end, where they pass into the cellular texture of the lung and lose their cartilaginous rings. The right bronchus was shorter than the left, as well as narrower. It would be very interesting to know whether the lungs are also divided into four parts, or only into two as is the rule; but having found no trace of this organ in the dry body I can say nothing of its form. Of the other viscera, I have found in sufficiently good state of preservation the oesophagus and the stomach. The first is 6 inches long, a large channel without any peculiarity ; but the second has also its peculiar configuration. It is formed by a great oviform sac, which is extended at both ends into a perpendicular pouch. The pouch of the left side, near the entrance of the oesophagus, is of the size of a pigeon's egg, but not very strongly separated from the central sac. The internal surface is somewhat rugulous, but the wrinkles are very fine and irregularly disposed. The central sac has a length of |