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Show 3 6 4 MR. C. TATE REGAN ON THE FISHES [Nov. 28, So long as they were supposed to be a fresh-water group, the geographical distribution of the Galaxiidfe was considered to be of considerable interest, occurring as they do in the Southern half of Australia, Tasmania, New Zealand and the neighbouring islands, Chile, Patagonia and the Falkland Islands, and at the Cape of Good Hope. The occurrence of Galaxias maculatus in the sea has been recorded by Valenciennes and by Philippi, off the Falklands and off the coast of Chile respectively. The observations of Johnston in Tasmania and of Hutton and Clarke in New Zealand are to the effect that Galaxias attenuatus descends to the sea periodically to spawn. Mr. Rupert Vallentin has seen shoals of little fishes, which I identify with the Galaxias gracillimus of Canestrini, in the sea at the Falkland Islands. Recently Galaxias brevipinnis has also been found to be marine, G. bollansi, described by Hutton from the Auckland Islands, proving to be identical with this species. The Galaxiidse present many analogies to the Salmonidfe of the Northern Hemisphere, both being circumpolar groups of marine origin which are establishing themselves in fresh-water. In both families we meet with non-migratory forms which appear to have finally left the sea and with others which return to the sea periodically; but whilst the migratory Salmonidfe are anadromous, the migratory Galaxiidfe, on the contrary, are catadromous. The enormous range of variation in the fresh-water Salmonidfe renders the delimitation of species a matter of great difficulty, and so it is with the Galaxiidfe, with the similar result that a large number of nominal or insufficiently defined species have been described. In some species numerous small blackish spots on the body and fins, due to the presence of parasitic organisms, are almost always present, and have been mistaken for colour-markings characteristic of the species (e. g. G. lynx and G. olidus). The burrowing- habits of a species of Galaxias have been recorded by T. S. Hall (Viet. Nat. xviii. 1900, p. 65), who states that, according to the observations of Mr. Russell Ritchie of Launceston, in Tasmania Galaxias have been dug up in moist peaty soil, and swim when placed in water. As many as twelve at a time have been dug up in one place and lived in water in a pickle-jar for various periods up to three days. The loss of the ventral fins and the small eyes of the New Zealand Neochanna apoda, which burrows in damp clay, show its special adaptation to similar habits. The material on which the present revision is based consists of the specimens in the British Museum, including all the types described by Richardson and by Gunther, as well as a series of specimens from Tasmania, sent by Mr. R. W. Johnston in 1880, representing the species described by him, and typical examples of G. nigothoruk Lucas and G. bollansi Hutton. A large series of specimens has been received from the Australian Museum, including the types of G. occidentalism G. waterhousei, and G. kayi. |