214 FAUNA OF NEW ZEALAND. 



tractile, though in a less degree than in Callioni/tnus, and without 

 giving a downward inclination to the mouth. Indeed, the struc- 

 ture of the jaws generally is much like that which exists in the 

 genus just mentioned. The gape is pretty large, and extends 

 nearly as far back as the anterior edge of the orbit. The under- 

 jaw is rather more acute than the upper one, and a very little 

 shorter ; it is bordered by a thin membranous lip, which widens 

 towards the angle of the mouth, and folds back when the orifice 

 is shut. The nostrils are situated a short way before the eye, and 

 just above the upper edge of the preorbitar. The posterior open- 

 ing is small and oval, and may be easily mistaken for one of the 

 pores which are scattered over the neighbouring scaleless parts : 

 the anterior opening is contiguous to it, and scarcely to be dis- 

 cerned, being almost hidden by a minute membranous point. A 

 small cluster of pores between the anterior angles of the orbits 

 may have been mistaken by Forster for the nostrils. His expres- 

 sion is, " nares inter oculos, contiguce." The upper and lower jaws, 

 branchiostegous membranes, preorbitars, disks of the preopercula, 

 and narrow space between the eyes, are covered with scaleless 

 membrane, dotted irregularly with minute pores. A double row 

 of these pores exists on the middle of each limb of the lower jaw ; 

 moderately large scales cover the cheek close to the orbits, and run 

 forward even a little farther than the angle of the mouth. The 

 scales of the operculum and suboperculum are somewhat larger, 

 and completely conceal the junction of the two bones. The inter- 

 operculum is equally scaly, but being slightly narrower its extent 

 is readily perceived. The disk of the preoperculum has a deeply 

 lunate form, and is augmented by a very thin scaleless membran- 

 ous border. No vestige of any spinous process exists on its 

 rounded edge. The whole gill-cover has an obtuse semi-oval form ; 

 and its thin, flexible, rounded edge projects far over the gill- 

 opening, and fits so closely to the pectoral region as to conceal the 

 opening, though it is very large, arid runs forward to the root 

 of the tongue. The gill-covers, being scaly to their extreme edges, 

 blend imperceptibly with the scales at the base of the pectoral fins, 

 giving no indication of the existence of the aperture till the flap is 

 raised; but on each side of the nape the opening, which runs for- 

 ward there, gapes somewhat like the valve of a mya. All this is 

 faithfully represented in George Forster J s figure ; but there is an 

 ambiguity in J. R. Forster's notes, which has led Cuvier to think 

 that the branchial aperture was restricted to a tubular opening, as 

 in Ccdlionymus. The passage is " opercula squ-amosa, calcari 



