Fig. 384.—Neoceratodus forsteri (Günther). Australia. Family Ceratodontidæ. (After Dean.)
Fig. 385.—Archipterygium of Neoceratodus forsteri Günther.
In 1870 the Barramunda of the rivers of Queensland was described by Krefft, who recognized its relationship to Ceratodus and gave it the name of Ceratodus forsteri. Later, generic differences were noticed, and it was separated as a distinct group by Castelnau in 1876, under the name of Neoceratodus (later called Epiceratodus by Teller). Neoceratodus forsteri and a second species, Neoceratodus miolepis, have been since very fully discussed by Dr. Günther and Dr. Krefft. They are known in Queensland as Barramunda. They inhabit the rivers known as Burnett, Dawson, and Mary, reaching a length of six feet, and being locally much valued as food. From the salmon-colored flesh, they are known to the settlers in Queensland as "salmon." According to Dr. Günther, "the Barramunda is said to be in the habit of going on land, or at least on mud-flats; and this assertion appears to be borne out by the fact that it is provided with a lung. However, it is much more probable that it rises now and then to the surface of the water in order to fill its lung with air, and then descends again until the air is so much deoxygenized as to render a renewal of it necessary. It is also said to make a grunting noise which may be heard at night for some distance. This noise is probably produced by the passage of the air through the œsophagus when it is expelled for the purpose of renewal. As the Barramunda has perfectly developed gills besides the lung, we can hardly doubt that, when it is in water of normal composition and sufficiently pure to yield the necessary supply of oxygen, these organs are sufficient for the purpose of breathing, and that the respiratory function rests with them alone. But when the fish is compelled to sojourn in thick muddy water charged with gases, which are the products of decomposing organic matter (and this must be the case very frequently during the droughts which annually exhaust the creeks of tropical Australia), it commences to breathe air with its lung in the way indicated above. If the medium in which it happens to be is perfectly unfit for breathing, the gills cease to have any function; if only in a less degree, the gills may still continue to assist in respiration. The Barramunda, in fact, can breathe by either gills or lung alone or by both simultaneously. It is not probable that it lives freely out of water, its limbs being much too flexible for supporting the heavy and unwieldy body and too feeble generally to be of much use in locomotion on land. However, it is quite possible that it is occasionally compelled to leave the water, although we cannot believe that it can exist without it in a lively condition for any length of time.
Fig. 386.—Upper jaw of Neoceratodus forsteri Günther. (After Zittel.)
"Of its propagation or development we know nothing except that it deposits a great number of eggs of the size of those of a newt, and enveloped in a gelatinous case. We may infer that the young are provided with external gills, as in Protopterus and Polypterus.
"The discovery of Ceratodus does not date farther back than the year 1870, and proved to be of the greatest interest, not only on account of the relation of this creature to the other living Dipneusti and Ganoidei, but also because it threw fresh light on those singular fossil teeth which are found in strata of Triassic and Jurassic formations in various parts of Europe, India, and America. These teeth, of which there is a great variety with regard to general shape and size, are sometimes two inches long, much longer than broad, depressed, with a flat or slightly undulated, always punctated, crown, with one margin convex, and with from three to seven prongs projecting on the opposite margin."