DR. RICHARDSON'S DESCRIPTION OF AUSTRALIAN FISH. 75 



jaws, though but slightly longer, are curved. A few very short, conical and bluntish, 

 but scarcely larger canine teeth stand among the others, near the symphyses of both 



jaws those in the anterior row pointing directly forwards, the posterior ones backwards. 



There is a transverse belt of teeth in close-cut pile {en velours ras) on the chevron of 

 the vomer, and a short longitudinal one at right angles to it on each palate bone. The 

 delicate and hair-like upper and lower pharyngeal teeth are also in villiform patches. 

 Tongue smooth. 



Gill-covers.— The upper limb of the preoperculum and the posterior half of its lower 

 limb are finely serrated, the teeth being a little coarser at the angle, which is moderately 

 rounded off. The scaly integuments are continuous with the cheek, and entirely con- 

 ceal the bony structure of the preoperculum ; but in the skeleton an elevated ridge is 

 seen pervading both limbs, and their thin posterior borders are transversely fluted and 

 undulated. The edges of the interoperculum and suboperculum are sUghtly curved, and 

 their posterior halves finely serrated. The operculum terminates in three short, flat, 

 delicate triangular teeth, so fragile that they are seldom all entire. The middle one is 

 the largest ; the upper one forms the angular point between the upper and posterior 

 margins of the bone, and is inconspicuous in the recent fish. The cartilaginous extre- 

 mity of the suboperculum projects beyond these spines, and forms the triangular tip of 

 the gill-cover. 



The supra-scapular bone is mostly concealed by the ordinary scales, but in the skeleton 

 it is deeply grooved, the groove forming a notch on its posterior edge, corresponding to 

 the commencement of the lateral line. The rest of the bones of the humeral chain are 

 without spines or serratures, and the scaleless margin of the gill-opening is narrow. The 

 soft axilla of the pectoral is also of small extent, and there is no visible bony plate there. 

 Scales.— The whole head is scaly, with the exception of the lips, infra-orbitars, a nar- 

 row circle round the eye, the soft stripe perforated by the nostrils, and the membranous 

 edges and folds of the gill-covers and jaws. On the forehead and snout the scales are 

 small and very densely tiled. They are larger on the cheeks, gill-covers and maxilla- 

 ries, smaller again on the lower jaw ; and the membrane connecting the limbs of that 

 bone is protected by a thick scaly band, which forks posteriorly, and crosses three of 

 the lower branchiostegous rays, permitting much smooth soft membrane to appear when 

 the jaws and gill-flaps are extended ; but when they are shut up, presenting nothing 

 but scaly surface. The scales of the body are largest anteriorly and near the lateral 

 line, smaller towards the contour of the back and belly, still more so before the pec- 

 toral and ventral fins, and smallest of all on the fins themselves. The scales in general 

 are square, except that the uncovered edge forms the quadrant of a circle. The base is 

 marked by from eight to fifteen fan-Uke streaks ; the surface is reticulated, the reticu- 

 lations being distinct only near the exterior margin, which is regularly ciliated by a 

 series of slender, straight, acute teeth. On the lateral line the scales are still more 

 nearly square, the exterior margin being almost straight. The tube of these scales is 



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