250 ZOOLOGY. 



whilst the least depth, on the peduncle of tlie tail, is hnt two-fifths of the greatest. The greatest 

 thickness is about one half of the greatest depth. The head is short, compressed like the body, 

 and rounded upon its anterior outline. It constitutes about one fifth of the entire length. The 

 nostrils are very much develojied, placed towards the upper surface of the head, and nearer to 

 the anterior rim of the eye than to the extremity of the upper jaw. The anterior opening is 

 subcircular ; the posterior one, subcrescentic. The eye is large and circular ; its diameter is 

 contained about three times in the length of the side of the head, and less than once in advance 

 of its anterior rim. The mouth is small and slightly oblique ; the posterior extremity of the 

 upper maxillary extending to a vertical line which would pass immediately in advance of the 

 anterior rim of the eye when the mouth is closed. There is one row of teeth upon each jaw; 

 on the dentary the teeth are much larger than on the intermaxillaries. Their form is flattened, 

 dilated towards their upper edges, which are provided generally with five subconical points, the 

 middle one being the longest, giving them the appearance of a digit. The palate is perfectly 

 smooth, and unprovided with teeth. The opercular apparatus is very much developed, and 

 subconvex upon its outer edge. The sub and interopercles are quite large, and occupy a prom- 

 inent place. The opercle is narrow above, expanded below, and slightly convex posteriorly. 

 The subopercle is curved, and in an oblique situation, with reference to the orientation of the 

 head. The gill openings are continuous under the hyoidal apparatus ; the branchiostegals, 

 three in number, are well developed, curved and flattened, the outermost being but a little 

 smaller and more slender than the innermost, or next to the opercular apparatus. 



The anterior margin of the dorsal fin is nearer to the extremity of the snout than to the tip 

 of the caudal fin ; it is much higher than long ; its upper edge is rounded or subconvex. The 

 rays bifurcate but once, and this for more than the half of their length. The anterior ray is 

 rudimentary, the second tmdivided. The adipose is slender, nearer to the base of the caudal 

 than to the posterior edge of the dorsal, and consequently situated behind the anal. The anal 

 is longer than the dorsal, and nearly as long as it is deep ; its exterior edge, convex anteriorly, 

 is subconvex posteriorly. Its anterior margin is situated backwards of the posterior edge of 

 the dorsal. There are very slight indications of a bifurcation of the second degree upon the 

 tip of its central rays; the first being rudimentary, and the second simple or undivided, as is 

 the case in the dorsal. The caudal fin, wliich constitutes about one fifth of the total length, is 

 deeply forked posteriorly; its lobes are rather rounded, and acute only upon their extremity. 

 The central rays, towards their extremity, exhibit a subdivision of the third degree. The 

 insertion of the ventrals takes place upon the middle of the abdomen, somewhat in advance of 

 the anterior margin of the dorsal. These fins are rather slender, with their tips acute, and 

 reaching the vent. Their central rays bifurcate twice. The origin of the pectorals is situated 

 near the inferior region of the thoracic belt. These fins are longer and more slender than the 

 ventrals ; their tip almost reaching the origin of the latter fins. Their anterior ray is simple ; 

 the central ones are but once bifurcated, and only towards the last third of their length. 



Br. Ill; D 10. 0; A 14; 3. I. 9. 8. I. 2; V7; PH. 



The scales are of moderate development, higher than long, subelliptical in shape, sometimes 

 very irregularly so. Ten or eleven longitudinal rows may be counted upon the line of the 

 greatest depth, and six or seven rows upon the peduncle of the tail. The lateral line is not to 

 be seen. 



The ground-color is olivaceous brown, with a silver band along the middle of the flanks, 

 extending from the upper angle of the opercular apparatus to the base of the caudal fin. The 

 cheeks, the opercles, and branchiostegal apparatus are silvery. A blackish stripe may be traced 

 all along the upper edge of the silvery band of the sides. The dorsal region is minutely dotted 

 with blackish, the dots being more particularly crowded upon the outline of the scales. These 

 dots extend to the upper surface of the head, and sparingly to the upper region of the thoracic 

 and abdominal regions; also to the inferior half of the peduncle of the tail. The dorsal, cau- 



