Art. XXVIII.—Notes on the Genus Callorhynchus, with a Description of an undescribed New Zealand Species.

By W. Colenso, F.L.S.

never seen before; I knew it was of the genus Callorhynchus, and, as I thought, distinct from C. antarctious (the only species of that genus then known to me), so I took a sketch drawing of it, with notes of its dimensions, etc., which I now give.

Callorhynchus dasycaudatus, mihi.

Total length, 3ft. 3in.; girth, (belly) 1ft. 5in.; length of pectoral fin, 9in.; first dorsal fin, 5in.; of attached bony ray, 7in.; length of tail, from angle in upper surface, 12in.; length from snout to anterior base of first dorsal fin., 9 ½in.; the bony ray in front of the first dorsal fin is partly separated from that fin, it is a little curved, and barbed slightly on the posterior edge; the extremity of the tail is free and feathered, which, being such a great peculiarity and so very characteristic of this species, has given rise to its pecific name. Whole fish silvery white, but highly iridescent; the fins of dark grey colour. It had no teeth, only palatal bones; a crayfish was found in its maw.

In its produced whip-like tail and barbed dorsal spine this species approaches more nearly to its northern congener, Chimæra arctica, Linn., formerly the type of the genus, before that Callorhynchus was separated from it by Cuvier.

Captain Hutton, in the work above cited (p. 74), gives as a character of this genus, “extremity of the tail distinctly turned upwards:” I scarcely understand this; such is certainly not the case in the one species mentioned by him as belonging to these seas, C. antarcticus; neither does any such character belong to C. australis,—another of our species, which I have also seen. Both of those species also differ widely from C. dasycaudatus, in the very large size of their pectorals, which overlap the base of their ventrals. Drawings of the tails of those two species I also give in the subjoined plate.

I also note that Dr. Richardson, in a paper on some new Tasmanian fishes, read before the Zoological Society in 1839, has another new species, C. tasmanius, which may also be found here in our seas; I have, however, never seen it. It differs from those two species last mentioned in the size of its pectorals; in which respect it approaches to C. dasycaudatus. Dr. Richardson gives the following characters to distinguish it from C. antarcticus (probably at that time C. australis was unknown to him)—“pinnis pectoralibus ad ventrales haud attingentibus; pinnâ dorsi secundâ pone ventrales incipienti, ante lobum anteriorem inferiorem pinnæ caudæ desinenti.” And then he adds: “This species agrees with the Callorhynchus smythi of Benne, figured in Beechy's Zoological Appendix, in the distance between the pectorals and ventrals, but is so unlike that figure in other respects that it is impossible to assign it to that species.” Of this last mentioned species (C. smythi), I know no more than what I have here quoted; should it be found in our seas, then, we may probably count on having five species of this genus.