10 DR. A. GTJNTHER ON THE BRITISH CHARRS. [Jan. 13, 



above the margin of the orbit, the diameter of which is nearly one"- 

 sixth of the length of the head, two-thirds of the extent of the snout, 

 and rather less than one-half of the width of the interorbital space ; 

 the latter is convex, with a rather prominent ridge along the middle, 

 and with a pair of series of pores. Snout compressed, conical, with 

 the jaws equal anteriorly. The maxillary extends to the vertical 

 from the hind margin of the orbit ; in the two largest specimens 

 (15-17 inches long) it reaches slightly beyond that vertical. It is 

 armed with 20-22 teeth of moderate size ; six teeth in each inter- 

 maxillary, fifteen in each mandible ; three pairs on the vomer, ar- 

 ranged in two longitudinal series slightly converging behind ; nine- 

 teen on each palatine bone, and six pairs on the tongue. Operculum 

 obtusely rounded behind, its length being two-thirds of its height ; 

 the suboperculum projects but little beyond the hind margin of the 

 opercle, its vertical width being one-half of that of the operculum. 



D. 13. A. 12. P. 13. V. 10. 



The origin of the dorsal fin is a little nearer to the end of the 

 snout than to the root of the caudal ; the length of its base is one- 

 third more than that of its last ray, and contained once and a fourth 

 in that of the fourth ray. The fifth and sixth rays form an acute 

 point, and the upper margin of the fin is straight. The first ray is 

 rudimentary, the second half the length of the third, the third two- 

 fifths the length of the fourth, the fifth simple, the sixth branched, 

 the last split to the base. The distance of the adipous fin from the 

 dorsal is but little more than twice the base of the latter. 



The origin of the anal fin is exactly in the middle between the root 

 of the caudal and that of the outer ventral ray ; the length of its 

 base is somewhat less than that of the dorsal, and is contained once 

 and a fourth in the length of the fifth ray. 



Caudal fin forked, one of the middle rays being two-fifths as long 

 as the outer ones, the length of which is contained six times and a 

 half in the total ; lobes pointed. 



The base of the pectoral is entirely free, and not overlapped by the 

 gill-cover apparatus; it terminates at a considerable distance from 

 the vertical from the origin of the dorsal, equals the length of the 

 head without snout, and is contained once and a third in the distance 

 between its root and that of the ventral. 



The ventral is inserted beloio the middle of the dorsal. 



A specimen, 12 inches long, from the same locality, agrees very 

 well with the one first described ; its operculum, however, is as long 

 as high, and the length of the pectoral fin is nearly one-half of the 

 distance between its root and that of the ventral. 



An immature specimen, 10 inches long, differs widely from the 

 preceding, its body and its head being much more elongate. The 

 length of the head is more than the height of the body, the 

 former being one-fifth, the latter one-sixth of the total length ; the 

 operculum is longer than high, and the height of the head above the 

 mandibulary joint is less than the distance between the posterior 

 margin of the orbit and the end of the operculum ; the maxillary ex- 



