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Show 392 PROF, F L O W E R O N A N E W [May and would be the means of obviating in future the confusion at present prevails for want of it." The following papers were read :- 1. On the Cranium of a new Species of Hyperoodon from the Australian Seas. By W I L L I A M H E N R Y F L O W E R , LL.D., F.R.S., P.Z.S., &c. [Received April 18, 1882.] Dr. Giinther has been so good as to submit to my examination the cranium of a Cetacean lately added to the British-Museum collection which presents sufficient interest to justify its being brought before the notice of this Society. The specimen was found upon the sea-beach of Lewis Island in Dampier Archipelago, North-western Australia. Unfortunately the cranium is in a greatly mutilated state, having evidently been rolled for a considerable period among pebbles and sand, from which cause many of its most important characters are destroyed. The lower jaw is wanting. The whole of the elongated narrow part of the rostrum is broken away. There is therefore nothing remaining to indicate the character of the dentition. Many prominent parts of the cranium, especially the supraorbital ridges, are worn down to such an extent that their contour is completely destroyed. This, as seen in figure 1 (p. 393), is carried to a greater extent upon the right than the left side. The slender jugal arches and the petrotympanic bones have disappeared. There is, however, enough remaining to show that it does not belong to any known species, and also to indicate, as far as they may be inferred from the cranium alone, its affinities. It should be premised that the animal to which it belonged was not very aged, as the sutures are mostly open; but there is no reason for supposing that it had not arrived at its full size. It is evidently one of the Ziphioids ; and as the characters of the four generic modifications of this group are plainly indicated in the conformation of the upper surface of the cranium (see ' Transactions of the Zoological Society,' vol. viii. p. 203), which is here well preserved, there is no difficulty in recognizing that it is neither a Berardius, nor a Ziphius, nor a Mesoplodon, but that it comes so near to Hyperoodon that it is only with animals of that genus that it will be necessary to compare it. An adult skull of the common species, H. rostratus, in the British-Museum collection, which presents all the typical characters of its kind, will serve very well for the purpose. Although the proportions differ somewhat, in general size the two are nearly equal, the H. rostratus, on the whole, having the advantage. In the posterior or occipital aspect, the new cranium differs from that of H. rostratus in being narrower and somewhat hio-her, |