FISHES OF HAWAIIAN ISLANDS. 
219 
in lower jaw; canines sometimes as few as 5 in number on each side; posterior nares narrow, vertical 
slits close in front of rim of orbit, and on a level with upper rim of pupil; anterior nares small, circular, 
and the. distance between posterior and anterior nares 5 in orbit; interorbital space convex, its width a 
little less than orbit, divided into areas by a series of low, thin ridges, one of these, quite as long as 
snout, extending forward along median line of occiput to about the vertical from posterior margin of 
orbit; on each side of this, a little behind its anterior end, begins a curved ridge which runs forward 
and outward to about the vertical from the hinder edge of the pupil, and thence forward and inward 
to the median line between the anterior nares, these symmetrical ridges forming a pear-shaped figure 
with its pointed end directed forward; on each side, at the greatest convexity of the above ridges, at 
the vertical of the posterior margin of the pupil, begins another ridge which runs straight forward and 
outward close to tiie antero-dorsal margin of the orbit, then curves inward and forward inside of the 
nares to a point in advance of the anterior nares and not far from the middle one; suborbital ring narrow; 
posterior edge of preopercle nearly vertical and straight, directed a little downward and backward and 
very slightly curved backward near its posterior end, producing a prominent rounded angle, both edges 
closely serrated, the serrations strongest, almost in the form of small spines, at the angle and at the ridge 
of the opercle forming a rounded and obtuse lint marked angle, with inferior edge serrated; opercle 
with slightly diverging ridges, the lower nearly horizontal and a little more strongly developed than 
the upper, both ending in small spines; gillrakers 13 on the anterior limb of first arch, the longest 
about 3 in eye; peritoneum black; scales large, thin, cycloid, very deciduous; interorbital space, snout, 
and lower jaw, and apparently the maxillary and opercles, scaleless; cheek with large, thin, embedded 
scales; second dorsal, anal, and caudal scaly on their basal parts; lateral line high up and continued on 
to basal past of dorsal fin; origin of first d< irsal fin over root of pectoral, its third spine probably longest, 
at least half as long as head, the spines slender and weak; origin of second dorsal a little in front of 
origin of anal, the rays heavy; first spine of anal short, the second longer, 1.5 in orbit, the soft rays 
thick; caudal deeply forked, the longest rays at least half length of head, and (the ends of the rays 
of second dorsal, of anal, and caudal all injured); upper end of root of pectoral about on a level with 
lower edge of pupil, the width of the base less than half orbit, the longest rays (injured at tips) at 
least two-ninths of Ixmy length; root of ventrals under root of pectoral; ventral spine with its outer 
edge densely serrate, the soft rays more than half as long as head. 
Color in alcohol, though the scales are nearly all off,' the back and upper part of side light 
brownish, with black lines at the edge of the fallen scales; top of head and snout dusky; sides of head 
and lower three-fifths of trunk and tail silvery; first dorsal fin blackish in the distal half, the other 
fins a little dusky; mouth cavity not dark, the gill-cavity a little dusky. 
A second, smaller specimen differs from the type in having only 5 instead of 9 canines in each 
lower jaw, its depth a little greater, orbit larger, gillrakers a little shorter. Aside from some very 
slight differences in flic proportions, it agrees in even minutest details with the type. 
Length 3.75 and 5.5 inches. Described from examples dredged at stations 3472 and 3476, in 295 
and 298 fathoms, by the Albatross in 1891 off the Hawaiian Islands'. (Gilbert and Cramer.) 
This species is said to lie close to Sgnai/rops japonica of Steindachner and Ifdderlein, differing from 
it, among other characters, in the serrated ventral spine, large number of canine teeth, greater length of 
second anal spine, in the color, the relative development of the 2 opercular ridges, and the absence 
of black color in the mouth cavity. 
Melanostoma argyreuni Gilbert & Cramer, I'roc. l\ s. Nat. Mus., XIX. 18%, lit',. PI. XXXIX, fig. 3, Albatross stations 3472 
and 3476 , off the Hawaiian Islands, in 275 and 2 g 8 fathoms. (Type. No. 47732 U.S.X.M.) 
Family LX. SFKIvWIDH. The Sen Hasses. 
Body obloug, more or less compressed, covered with adherent scales of moderate or small size 
which are usually but not always ctenoid; dorsal and ventral outlines usually not perfectly correspond¬ 
ing; mouth moderate or large, not very oblique, the premaxillary protractile and the broad maxillary 
usually not slipping for its whole length into a sheath formed by the preorbital, which is usually 
narrow; supplemental maxillary present or absent; teeth all conical or pointed, in bands, present on 
jaws, vomer, and palatines; gillrakers long or short, usually stiff, armed with teeth; gills 4, a long slit 
behind the fourth; pseudobranchias present, large; lower pharyngeals rather narrow, with pointed 
teeth, separate (except in Centrogenys ); gill-membranes separate, free from the isthmus; branchioste- 
