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Show 1869.] DR. MACDONALD ON A NEW GENUS OF MUGILIDAE. 39 side, the left apparently overlapping the right. Dorsal fins two, distinct, the anterior consisting of four rigid spines, and the posterior of eight soft rays and one rigid in front. Pectoral fins small and scaly to the tip. Abdominal fins with five soft rays, fronted by one spinous. Anal with ten rays, the first alone of which is spinous. No lateral line visible as in the Mullets generally. Scales large, both the longitudinal and transverse measurements reaching T 8 7 of an inch, with a mucus-groove on the inner surface of each, fulfilling the office restricted to those that form the lateral line in other fishes. On reviewing Dr. Giinther's Synopsis of the characters of the three genera of Mugilidae, viz. Mugil, Agonostoma, and Myxus, I find that Ika loa is not strictly conformable to any of them, but apparently takes up an intermediate place between Agonostoma and Myxus. Thus the cleft of the mouth extends on the side of the snout to the orbit as in Agonostoma, dissociating it from Myxus ; the teeth of the upper jaw, however, are in a single series, the anterior margin of the lower jaw is sharp, as in Myxus, and the upper lip is notched to receive the mesial prolongation of the lower, still further distinguishing it from Agonostoma. I therefore conceive that Ika loa deserves a place in a new genus, for which I propose the name of Gonostomyxus, retaining the native word, loa loa (black), for the species. The following diagnosis of the genera of Mugilidae may be given to illustrate the view here expressed, adopting Dr. Giinther's characters:- I. Cleft of the mouth extending on the sides of the snout, but not to the orbit. a. N o true teeth in the jaws Mugil. b. Small teeth in a single series in the upper jaw, and sometimes in the lower and on the palate. Anterior margin of the mandible sharp Myxus. II. Cleft of the mouth extending on the sides of the snout, beyond, to, or nearly to, the orbit. a. Small teeth in a single series in the upper jaw, in two lateral crescentic clusters in the lower jaw, and in a short irregular transverse row on either side of the vomer. Anterior margin of the mandible sharp ... Gonostomyxus. b. Small teeth at least in one of the jaws, and sometimes on the palate. The lower lip with the margin rounded, not sharp Agonostoma. Of course the further discovery of species referable to Gonostomyxus may suggest some modification of the characters above given. I shall now give a brief description of T/ca-loa-fishmg on the Wai Manu. The Maroons of Jamaica capture the freshwater Mullet with a pronged spear, pursuing it under water; but the Feejeeans take the Ika loa very skilfully in a small net, assisted by outlying divers who decoy the fish into the net, cutting off their escape. The men of Soloira, under the Vuni Chief of Vun Mbua, are famous for their knowledge of the habits of the "Black Mullet" and their success in fishing for it. It will be necessary here to give an idea of the construction of the net. It is very simple, consisting merely of a piece of net once |