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U. S. P. E. E. EXP. AND SUEVEYS—ZOOLOGY—GENEEAL EEPOET. 
either side of the lower jaw being larger than the rest and situated more inwardly; and hy the 
presence of teeth on the palatine hones, which do not exist in the mackerels. 
PELAMYS LINEOLATA, Grd. 
Spec. Ciiau. —Head sub-conical; gape of mouth somewhat oblique; jaws nearly even; posterior extremity of maxillaries 
extending to a vertical line drawn within the posterior rim of the orbit. Origin of anterior dorsal situated slightly in advance 
of the base of the pectorals. Anterior margin of anal placed opposite the posterior margin of the second dorsal. Eight finlets 
above the tail, and seven under it. Bluish black above, with longitudinal blackish streaks ; silvery on the sides, and yellowish 
beneath. 
The only specimen of this species which has come under our observation as these sheets were 
passing through the press, measures about eleven inches in total length. The body is most 
gracefully elongated, rather slender, very much compressed., and sub-fusiform in its profile. 
The greatest depth, taken at the insertion of the ventral fins, is contained six times in the total 
length; the greatest thickness, at the same region, being about the half of the depth just 
alluded to. 
The head constitutes about the half of the total length; the gape of the mouth is somewhat 
oblique upwards, the snout being sub-conical, and the jaws nearly even; the lower one having 
a tendency to project very slightly beyond the upper. The posterior extremity of the maxillar 
bone, which is rounded, falls evenly with a vertical line drawn inwards of the posterior rim of 
the orbit. The teeth are rather distant and more slender on the upper jaw than on the lower, 
towards the apex of which two canine-like ones may be observed, one on either side, and some¬ 
what larger than the rest. The eye is moderate sized, sub-circular, its horizontal diameter 
entering about six times in the length of the side of the head; twice in advance of its anterior 
rim. The anterior nostril is very minute, situated midway between the apex of the rostrum 
and the centre of the pupil; whilst the posterior one, an elongated, vertical, sub-crescentic split, 
is placed somewhat in advance of the orbit, its sub-concave side towards the eye. The edge of 
the opercular apparatus constitutes an even curve. 
The origin of the first dorsal fin takes place upon a vertical line which would pass somewhat 
in advance of the base of the pectorals. It is highest anteriorly, diminishing gradually in 
depth backwards. It is somewhat longer than the head, hence its length is a little more 
than the fourth of the total length. A space of three-eighths of an inch exists between the 
two dorsal fins. The second dorsal is sub-triangular, a little longer than high, and is followed 
by eight finlets, the tip of the last of which reaching the base of the caudal fin. The anal, 
somewhat smaller than the second dorsal, is sub-triangular also, its anterior margin being 
situated nearly opposite the posterior margin of the latter mentioned fin. Seven finlets a little 
larger than the dorsal ones may be seen under the peduncle of the tail. The caudal is slender, 
its posterior margin having the shape of a very open crescent. The ventrals are moderate 
sized, their anterior margin corresponding to a vertical line drawn immediately behind the base 
of the pectorals. The pectorals themselves are rather short, sub-falciform and broad at the 
base. 
Br. VII: VII ; D XVIII, 13 ; A 12 ; 0 11, 1, 9, 8, 1, 12 ; V 1, 5 ; P 27. 
The scales, as already observed, are quite small and inconspicuous ; even those constituting 
the thoracic corselet require something more than a superficial glance before their presence is 
made obvious. The lateral line is somewhat undulated, although following a direct course from 
the upper region of the thoracic arch to the peduncle of the tail. It is nearer the dorsal outline 
