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Show 436 MR. F. E. BEDDARD ON THE [June 3, the keel is not deep as in many purely flying birds. Eurypyga has a very deep keel to the sternum. The clavicles have a large interclavicular piece which is prolonged in front as well as behind. Here, again, Podica appears to be peculiar, or rather to resemble Ardea, which has also an anterior and posterior interclavicular process. Among the supposed near allies of Podica, Colymbus and Podiceps have both a posterior interclavicular process only, which is present, though extremely small, in Rails. The pelvis of Podica is in some respects like that of many Rails; but in other particulars again it is Grebe- or Diver-like. The ilia in front (see fig. 5, p. 437, and fig. 6, p. 438) do not reach up to the top of the spines of the dorsal vertebrae ; each ilium also is deflected away from the vertebral column and overlaps several ribs. In most Rails that I have examined, the ilia completely cover the vertebrae, being fused with the summit of their neural spines; this is the case at any rate with Ocydromus and Aramides. In Tribonyx and Fulica the ilia do not completely cover up the dorsal vertebrae which they overlap ; but in both these forms the ilia approach each other at their anterior extremity, and are not deflected away from each other as they are in Podica. In this particular the pelvis of Podica is decidedly Colymbine. The general outline of the pelvis is as decidedly that of a Rail, being wider behind than in front; but in all the Rails which I have examined the pelvic bones are perfectly free from the ischia, though they do not extend very far behind the termination of the latter. In Podica there is in places a close union between the pubis and ischium of each side, amounting to a synostosis, while the pubic bones themselves extend for about an inch in length beyond the ischia, and are curved inwards towards each other. As regards the non-fusion of the pubis and ischia, the Divers are at one extreme and Podica at the other-the Rails occupying an intermediate position ; so that, although Podica is in some respects peculiar, it must be considered as coming nearer to the Rails than the Grebes. The backward extension of the pubes is, however, a Grebe-like character, though it is after all rather slight. The ilia of Podica end posteriorly in a strong blunt point on each side, about as long as the first two vertebra?, and there is no strong ridge, such as w e meet with in the Rails; the hinder part of the pelvis is smoothed and rounded. Although there are differences here from the Rails, it cannot be said that there are any marked resemblances to the peculiar pelvis of the Diver and of the Grebe. The anterior parts of the ilia together with the intervening vertebrae are narrower than the postacetabular portion of the pelvis; but the disproportion is certainly not so great as in most of the Rails: the long and narrow pelvis of Fulica ardesiaca, though it does not approach in shape that of Podica, does so in the proportion of the anterior and posterior regions ; so also that of Aramides, with which |