Note 12 — Chapter X · THE SCYPHOPHORI, HAPLOMI, AND XENOMI

Dr. Boulenger (Nature, Nov. 27, 1902) has the following note on Galaxias: "Most text-books and papers discussing geographical distribution have made much of the range of a genus of small fishes, somewhat resembling trout, the Galaxias, commonly described as true fresh-water forms, which have long been known from the extreme south of South America, New Zealand, Tasmania, and southern Australia. The discovery, within the last few years, of a species of the same genus in fresh water near Cape Town, whence it had previously been described as a loach by F. de Castelnau, has added to the interest, and has been adduced as a further argument in support of the former existence of an Antarctic continent. In alluding to this discovery when discussing the distribution of African fresh-water fishes in the introduction to my work 'Les Poissons du Bassin du Congo,' in 1901, I observed that, contrary to the prevailing notion, all species of Galaxias are not confined to fresh water, and that the fact of some living both in the sea and in rivers suffices to explain the curious distribution of the genus; pointing out that in all probability these fishes were formerly more widely distributed in the seas south of the tropic of Capricorn, and that certain species, adapting themselves entirely to fresh-water life, have become localized at the distant points where they are now known to exist. Although as recently as October last the distinguished American ichthyologist D. S. Jordan wrote (Science, xiv, p. 20): 'We know nothing of the power of Galaxias to survive submergence in salt water, if carried in a marine current': it is an established fact, ascertained some years ago by F. E. Clarke in New Zealand and by R. Vallentin in the Falkland Islands, that Galaxias attenuatus lives also in the sea. In New Zealand it periodically descends to the sea, where it spawns, from January to March, and returns from March to May. In accordance with these marine habits, this species has a much wider range than any of the others, being known from Chile, Patagonia, Tierra del Fuego, the Falkland Islands, New Zealand, Tasmania, and southern Australia.

"I now wish to draw attention to a communication made by Captain F. W. Hutton in the last number of the Transactions of the New Zealand Institute (xxxiv, p. 198), 'On a Marine Galaxias from the Auckland Islands.' This fish, named Galaxias bollansi, was taken out of the mouth of a specimen of Merganser australis during the collection excursion to the southern islands of New Zealand made in January, 1901, by His Excellency the Earl of Ranfurly.

"It is hoped that by giving greater publicity to these discoveries the family Galaxiidæ will no longer be included among those strictly confined to fresh waters, and that students of the geographical distribution of animals will be furnished with a clue to a problem that has so often been discussed on insufficient data. As observed by Jordan (l. c.), all anomalies in distribution cease to be such when the facts necessary to understand them are at hand.'

"Of the fresh-water species of Galaxias, eight are known from New Zealand and the neighboring islands, seven from New South Wales, three or four from south Australia, one from west Australia, two from Tasmania, seven from South America, from Chile southwards, and one from the Cape of Good Hope."