HvEMULON CHRYSOPTERON. 121 



margin above the median plane of the head. The nostrils are double, nearer to 

 the orbit than to the snout ; both are sub-oval, and the posterior is rather above 

 the median plane of the eye. The mouth is capacious in the longitudinal direc- 

 tion, but is much compressed and narrow in the transverse, "with lips tolerably 

 thick and fleshy. The upper jaw is longer than the lower, and receives its teeth 

 when the mouth is closed. Both are armed with a single row of pointed, rather 

 long, conical teeth ; those of the lower jaw are largest behind, those of the upper 

 are largest in front, and slightly incurved ; behind this row in each jaw is a broad 

 patch of minute, villiform teeth, closely crowded together, and extending about 

 one fourth the length of the lower jaw, and rather more than a fourth in the 

 upper. The pharyngeal teeth are small, conical, pointed, and directed backwards. 

 The tongue is small, pointed in front, and but slightly movable. 



The pre-opercle is large, with its angle round, and its ascending border nearly 

 vertical, slightly emarginate, and beautifully serrated. The opercle is nearly 

 sub-triangular, rounded behind, with its base upwards, and is separated from 

 the pre-opercle below by the inter-opercle. The whole head, except the lips 

 and space between the nostrils and snout, is covered with scales. The gill- 

 openings are rather contracted ; there are seven branchial rays. The supra- 

 scapular is rounded behind, rather small, but strongly serrated, and from it ascend 

 two or three series of small scales, which mark the separation of the head from 

 the body. 



The dorsal fin is single ; it begins with the root of the pectoral, and has thir- 

 teen spines, the first short, the fourth, fifth, and sixth more or less compressed 

 and curved ; the others are straight, and all are partially received in a groove of 

 scales ; there are fourteen soft rays, covered for some distance with scales. The 

 pectoral is thin, rather long, but it ends before the vent, and has seventeen rays. 

 The ventral fin arises back of the root of the pectoral, and terminates with it 

 behind ; it has one spine and five soft rays, the anterior ending in a short fila- 

 ment. The anal begins opposite the third dorsal soft ray, and has three spines 

 received in a groove ; the anterior is very short, and the others three times as long, 



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