OCR Text |
Show 1866.] DR. A. CARTE ON THE GENUS CHIASMODON. 37 its tip is free and of a greyish-yellow colour. There appear to be no vomerine teeth, no barbel, nor pseudobranchise. The pectoral fins, which contain twelve (?) very slender rays, are inserted immediately below the excavation in the posterior inferior margin of the operculum, its pointed extremity extending backwards for about 1-1 inch. The ventrals are so misplaced, in consequence of the great distension of the abdominal parietes of the fish, that it is impossible to give an accurate description of their normal position. In length they measure about nine-sixteenths of an inch, and contain about six delicate subequal rays. The anal fin, from the same cause, is greatly displaced: instead of holding its normal position along the ventral surface of the fish, it is completely separated from it and carried down on the distended and greatly thinned abdominal integument; and the points of its rays are so mutilated that .they cannot be measured with accuracy. The course of the intestine is distinctly visible through the semitransparent integument, running downwards and backwards to the anal orifice; both it and the anal orifice, as may be seen by reference to the accompanying figure (Plate II.), are also much displaced. As, for obvious reasons, it was not considered advisable to dissect this curious and interesting specimen, I cannot add any further particulars, in reference to the rest of the alimentary system, to those which have already been recorded by Mr. Johnson. The caudal fin is furcate, and contains about eleven principal rays, of which the longest measures about 1 inch. The lateral line runs for the greater part of its course straight along the centre of the body, but as it approaches the head it curves upwards behind the posterior superior margin of the operculum. inches. Total length of specimen from snout to extremity of tail .. 6-f Total length of head from snout to point of operculum.... 1-| Height of head -f Eye, diameter of its major axis T\ Length of longest tooth (fourth) in lower jaw \ Distance of first dorsal fin from muzzle, about 1-| Length of pectorals 1-^ Width of the base of pectorals -g- Distance of pectorals from muzzle 1-| Length of ventrals, about -| of caudal fin 1 The length of the enclosed fish (Scopelus macrolepidotus 1) . \0\ Depth at pectorals If In a subsequent letter received from Sir Leopold McClintock, dated from Port Royal, Jamaica, the 6th of November, 1865, he says, "They are not deep-water fish; both are well known at Dominica, more particularly the larger one (S. macrolepidotus 1), which is common. The smaller one (C. niger 1) is not common ; but the |