10 CATALOGUE OF FrSH. 



mad of the left rays, curving more tliau half-way across the throat, 

 and returning over the right operculum to the nape ; while the 13 

 anterior dextral rays sweep at once across to the left side, lying in 

 contact with the left gill-sac, and, consequently, interiorly or dorsad 

 of the rays which spring from the left hranch ; they then curve 

 backwards across the throat to the right side, where they protrude 

 a little beyond the edge of the other rnys. 



Gill-openings wider than those of Murci'va, and lower down, being 

 similar in appearance to those of Aiujidlhi. Brancliise, 4, with 5 open- 

 ings at their bases into the gullet. Pharyngeal bones armed with 

 minute teeth. Heart posterior to the branchiae, and jdaced between 

 the hinder lips of the gill-openings. The humeral arch is composed 

 of 2 slender bones, on each side, which do not meet their fellows on 

 the ventral line. Pectoral lin oval, of moderate size, sustained by 

 16 branching rays. 



Body nearly cylindrical ; the back carrying its roundness far 

 past the anus ; and tlie tail, which becomes more compressed 

 towards its extremity, retaining its lateral convexity, its tip being 

 conical. The dorsal and anal carry their height well down to the 

 tail, a slight increase taking place just before they suddenly slope 

 off, leaving the extreme point of the tail destitute of rays, but 

 edged above and below by a scarcely perceptible cutaneous seam. 

 The anus is placed at about one-twelfth of the whole length of the 

 fish, before the middle. The skin is smooth, without scales, and 

 without a visible lateral line. 



After long immersion in spirits, the specimen has a dusky 

 brown colour, darker on the back, paler on the belly, and without 

 spots. 



Tiie cfEcal stomach tapers to a point, and the pylorus opens ob- 

 liquely througli its coats, at its upper end, so as to form a valvular 

 obstruction to the regurgitation of the faecal matter. A spiral 

 valve exists in the lower part of the gut, like that which occurs in 

 the MurcEiKS. The long and slejider air-bladder is widest at its 

 lower end, near the anus, and tapers upwards to a hair-like j^oint. 

 It is 3^ in. long, and sends an air-duct from its middle to the oeso- 

 phagus. 



Teeth. Nasal disk circular, armed with about 15 crowded, round, 

 rather flat-crowned teeth of ditferent sizes, separated from the den- 

 tal surface of the vomer by a smooth line. The vomerine teeth 

 stand about 5 abreast ; but the anterior teeth being larger, the 

 dental band is wider there. The swelling folds of the soft palate 

 partly overlie the posterior vomerine teeth ; hence the artist has 

 represented the dental surface in fig. 8 as tapering more towards 

 the gullet than it does in reality. Palatine teeth smaller than the 

 nasal ones, not quite so flat on the crowns, and disposed so as to 

 form an elliptical plate, which has also been drawn in fig. 8 as too 

 taper, owing to the pouting lips concealing parts. There are, in 

 fact, 6 or 7 teeth abreast in the widest part of the plate, and 2 or 3 

 posteriorly. The dental plates of the mandible muster about 5 



