Notice of Ceratodus fosteri, Krefft, or Barramunda, of the Queensland Rivers.
Charles Knight, F.R.C.S., President, in the chair.
New members.—Edward Osborne Gibbes, Thomas E. Young, A. J. Woodhouse (London), Captain Gudgeon.
A number of valuable presentations were on the table, among them a magnificent folio volume of the Flora of Central Africa, presented by J. A. Tinne, Esq., of Ayburth, near Liverpool.
Dr. Hector drew attention to the articles with which the Museum had been enriched by the “Challenger” expedition. These consisted of specimens of different fishes, etc. The first was that of a large fish—the Ceratodus fosteri, Krefft, or Barramunda, of the Queensland rivers, of which Dr. Hector gave the following account:—
The fish to which I have now to draw your attention is one of the most interesting additions that has been made within modern times to this branch of zoological science. The first specimen was discovered in the beginning of 1870 in the north of Queensland, where it is known by the native name of the “Barramunda.” It appears not to be uncommon, as specimens have been obtained in several of the rivers, not only in the upper parts where the water is quite fresh, but also near the sea where it is brackish. It is a vegetable feeder, living on decaying leaves of gum trees and other myrtaceous plants, and yet, strangely enough, its flesh is described as excellent eating and resembling salmon. The chief interest attaching to this fish arises from the circumstance that it is the living representative of an intermediate class of amphibious animals from which in early times sprung fishes on the one hand, and true reptiles on the other. Unlike any other fish, it has a lung, but has also gills, thus possessing two distinct modes of purifying and oxygenating its blood.
We know that this is the embryonic condition of the lower forms of reptiles, and the persistence of this double breathing apparatus is probably suited to the condition under which this curious animal exists.
Thus Dr. Güther describes * that whilst Barramunda is in water sufficiently
[Footnote] * A. memoir of the entire organization of this interesting fish was presented to the Royal Society by Dr. Albert Günther, F.R.S., of which a short résumé will be found at page 222 of the Ann. and Mag. N. H. for March, 1871
pure to yield the necessary supply of oxygen, the function of breathing rests with the gills alone; but when the fish is compelled to sojourn in thick muddy water charged with noxious gases, which must be the case very frequently during the droughts which annually exhaust the creeks of tropical Australia, it commences to breathe air by its lung direct from the atmosphere, rising to the surface of the water from time to time for this purpose.
The skeleton of the Barramunda, and the construction of its heart, require it to be placed, as Dr. Günther has shown, among the ganoid fishes— a section of the cartilaginous fishes that was largely developed in early geological times. Notwithstanding its large size and well-developed fins, its internal skeleton is only represented by a long, tapering, cartilaginous cord, without distinct vertebræ, and with only a simple capsule for a brain case. The appendages of this central structure are, however, encased in a thin crust of bone, so that the ribs and processes for the attachment of the limbs, and the jaws for the attachment of the teeth, are slightly rigid.