64 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 



readily felt than seen : the angle at bottom is rounded, and rather exceeds a right ano-le • a 

 vertical from the angle would form a tangent to the posterior edge of the orbit : the ascending 

 margin is not quite straight, bending slightly inwards a little below the middle. The opercle 

 terminates posteriorly in a very obtuse angle, and shows some indication of two very minute 

 flattened points, which, however, do not project beyond the membrane : from the lowermost of 

 these points the margin of the subopercle passes obliquely forwards to form a continuous curve 

 with that of the interopercle, which is tolerably well developed. Gill-opening of moderate size: 

 the branchial membrane, which apparently has only four rays, has a shallow notch in front, and 

 passes continuously from one side to the other, without being attached to the isthmus. 



The lateral line commences at the upper angle of the opercle, and, inclining upwards, runs 

 parallel, not to the dorsal line which can hardly be distinguished, but to the upper edge of the 

 dorsal fin, its distance from which is contained about three times and a half in the entire depth; 

 it terminates a little before the termination of that fin. Cranium, snout, cheeks, pieces of the 

 opercle, the body, and all the vertical fins, covered with finely ciliated scales ; those on the 

 crown and snout small, but those on the opercle and body large ; the latter arranged in oblique 

 rows ; about twenty-seven in a longitudinal line from the gill to the caudal, and about fourteen 

 in a vertical one from the dorsal to the ventral line : a scale taken from the row beneath the 

 lateral line, and about the middle of the body, is of an oblong form, its breadth exceeding its 

 length, with the free edge dotted and finely ciliated, the basal margin rather deeply crenated, 

 the crenations separated by seven striae, which are carried on for only a short way, and do not 

 converge to a fan. The scales on the dorsal and anal fins are small and closely compacted ; 

 those on the former arranged obliquely, but the line of obliquity is in the opposite direction to 

 what it is on the body. 



The dorsal fin commences in a line with the posterior angle of the opercle, and occupies a 

 space equalling half the entire length : the height of the spinous portion is nearly uniform, but 

 slightly increases backwards; between the tips of the spines, the membrane is a little jagged : 

 the soft portion is scarcely more than one-third the spinous in length, but is somewhat higher, 

 terminating upwards in an acute angle ; the longest of the soft rays is about half the depth of 

 the body, the dorsal fin itself not included. The anal answers to the soft portion of the dorsal, 

 which it exactly resembles; it has two spines in front, the first of which is very short, and 

 scarcely more than one-third the length of the second, which itself is shorter than the soft rays ; 

 the second spine is stouter than any of the dorsal spines. These two fins terminate in the same 

 vertical line. The caudal appears to have been square, but the rays are worn at the tips, so that 

 its exact form cannot be ascertained; it is coated with scales for four-fifths of its length from 

 the base. Between the dorsal and the caudal fins is a space equalling not quite one-third the 

 depth of the body. Pectorals attached a little behind the opercle, and a little below the middle; 

 slightly pointed ; about the length of the head or rather shorter ; the first ray only half the 

 length of the second ; fourth and fifth longest ; all the rays, with the exception of the first two 

 and the last two or three, branched. Ventrals attached a little further back than the pectorals ; 

 the first soft ray prolonged into a filament reaching to the commencement of the anal ; the 

 spine is about half the length of the filamentous ray, and about two-thirds that of the second 

 soft ray. Between these fins is an oval lanceolate scale about one-third their length ; and in 

 their axillae another elongated one, narrower and more pointed than the former, and rather 

 exceeding it in length. 



