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Show Mr. F. E . B e d d a r d , F.R.S., x'ead a third of a series of papers on the Anatomy of the Lacertilia, which dealt with points in the vascular system of Chamceleon and other Lizards. A communication from Mr. A. D. I mms, B.Sc., contained notes on the gill-rakers of Polydon, in which he pointed out that these processes in this Fish were setiform structures disposed along both the anterior and posterior edges of the first four branchial arches and along the anterior edge of the fifth arch also. Each gill-raker consisted of a basal portion, which was attached by means of elastic fibres to the cartilage of the branchial arch, and a long, free shaft portion which formed its principal part. The matrix of a gill-raker contained numerous lacunar spaces which were connected with one another by means of canaliculi, and in the shaft portion it contained, in addition, a series of anastomosing channels in which lay blood-capillaries and some loose connective-tissue. The mucous membrane covering a branchial arch was prolonged over each gill-raker in the form of a complete investing coat. The gill-rakers of Polydon were exoskeletal structures, and they appeared to be composed of a substance closely allied to osteo-dentine, and their presence on the branchial arches might perhaps be accounted for on the supposition that the ectoderm forming the outer portions of the gill-clefts had migrated on to the inner margins of the branchial arches. The food of Polydon consisted of microscopical organisms, and the gill-rakers function as a straining mechanism which effectually barred the entry of such particles into the gill-cavities. A paper was read by Dr. W. G. R id ew o o d , F.Z.S., on the " Cranial Osteology of the Elopidce, and Albulidce, with Remarks on the Morphology of the Skull in the Lower Teleostean Fishes generally." The paper included a detailed account of the skulls of Elops saurus, Megalops cyprinoides, Albula conorhynchus, and Bathythrissa dorsalis, together with remarks, generalisations, and criticisms of published accounts of the skull-bones of fishes, based mainly upon an examination of the skulls of 20 species of fishes selected from among the most primitive families of the existing Malacopterygii. Among other features pointed out by Dr. Ridewood was the fact that in Elops and Albida, although the parietals met in the middle line, the supraoccipital extended forward beneath them to reach, and even to underlie, the frontal bones ; in the former genus and in Megalops the supraoccipital also touched the alisphenoid bones. The posterior temporal fossae were so great in Megalops that they reached the orbitosphenoid bone, and they communicated freely above the brain-case. A careful comparison of the skulls of Bathythrissa and Albtda confirmed the close relationship existing between these genera suggested by Boulenger in 1898. Except that in some few respects the bones were modified in correspondence with a deep-sea habit, the skull of Bathythrissa bore a very close resemblance to that of Albula. |