FISHES OF HAWAIIAN ISLANDS. 
661 
dorsal; scales on head very large, more than twice those on sides of body; they entirely invested 
head, including snout and mandible, except the gill-membranes. 
Dorsal brownish on body and top of head; belly, breast, opercular and gular membranes blue- 
black; snout and side of head also blackish, this being especially marked in young examples, where 
the deeper lying black pigment is seen through the translucent surface tissues; mouth and gill-cavities 
and abdominal cavities lined with black. 
In the 6 specimens obtained, the ventral rays are constantly 9 in number; the dorsal formula is 
ii, 8 in 2 specimens, ii, 9 in 4; the pectoral varies from 17 to 19, and the gill-rakers in all except the 
type, number 6 or 7 on the vertical limb, 22 to 24 on the horizontal limb of the outer arch. 
The present species resembles in appearance Bathygadus cottoides Gunther, from New Zealand and 
the Kermadec islands, but differs generically in the presence of a slit behind the last gill, and in the 
position of the scapular foramen; Like B. cottoides, it has a very soft cavernous head, with excessive 
development of the system of sensory canals, and very thin delicate membrane bones. The head is also 
very wide and subquadrate, with nearly vertical cheeks, and lacks any trace of a mandibular barbel. 
In addition to the generic characters, the 2 species differ in the number of dorsal and pectoral fin-rays, 
the number of gill-rakers, and the relative lengths of snout, interorbital width, and orbital diameter. 
Direct comparison of specimens has not been possible. Because of the presence of a slit behind the 
last gill, and the position of the scapular foramen, which is wholly within the hypercoracoid, this 
species is placed in the genus Gadomus Began. Its relations with G. longifilis, the type of Gadomus, 
seem, however, remote, as is indicated by the absence of a barbel and by the entire habit of the fish. 
The species was taken at the following stations: Nos. 3977, vicinity of Bird Island, 876 to — 
fathoms; 4007, vicinity of Kauai, 508 to 557 fathoms; 4141, vicinity of Kauai, 437 to 632 fathoms; 4151, 
vicinity of Bird Island, 313 to 800 fathoms. 
Melanobranchus micronema, new species. Fig. 258. 
Type, 235 mm. long, from station 4094, Pailolo Channel, between Maui and Molokai, depth 753 to 
787 fathoms; type, No. 51643, U. S. Nat. Mus. 
Head 5.2 in total length; depth 6.7; head and trunk 3.2. D. n, 10; P. 18; Y. 8. 29 scales in 
an oblique series upward and forward from first anal ray to base of dorsal; pyloric caeca very large, 
9 in number. 
Head wider and somewhat softer than in Gadomus melanopterus, the greatest width of head exceed- 
ing length of snout and eye, contained 1.7 times in length of head, 0.7 the greatest depth; snout wide 
and low, bluntish at tip, its greatest width equaling distance from its tip to posterior margin of pupil; 
longitudinal diameter of eye equal to interorbital width, 4.5 in the head; snout longer, 3.6 in head; 
mouth terminal, but little oblique, the mandible everywhere included, shutting wholly within the 
premaxillary teeth; maxillary extending beyond vertical from hinder margin of eye a distance equal 
to 0.6 diameter of orbit; mandibular barbel minute, its free portion not more than half a millimeter 
long; teeth minute, equal, slightly depressible, in narrow bands in each jaw, the premaxillary band 
reaching angle of mouth, the mandibular band shorter; palate toothless; preopercle narrow with 
parallel margins; opercle and subopercle terminating posteriorly in weak spinous points, which are 
concealed in the membrane; gill-membranes joined anteriorly, but free from isthmus, across which 
they form a moderate free fold; outer set of gill-rakers very long and slender, the longest .6 diameter 
of eye; gill-rakers 35 in number, 6 or 7 on vertical limb of arch; branchiostegals 7; gills 4, a wide 
slit behind last arch; no pseudobranchise ; scapular foramen between the hypercoracoid and the 
hypocoracoid. 
Origin of first dorsal slightly in advance of base of pectorals; first dorsal spine very short and con- 
cealed, the second elongate, filiform, .9 length of head; remaining rays forked as well as articulated, 
except the last 3, which are simple; interval between the dorsals a trifle wider than that separating the 
successive rays of the second dorsal; second dorsal rays very high, the longest uninjured ray .3 length 
of head; tail injured, blunt at tip, surrounded by the fin; anal origin vertically below thirteenth ray 
of second dorsal, the rays all very short; upper pectoral ray very elongate, reaching thirty-sixth ray of 
second dorsal, its length (85 mm.) contained 2.7 times in total length; outer ventral ray also elongate 
and filamentous; injured in the type, its broken tip reaching base of fifth anal ray, 40 mm. long; a very 
short interval separates vent from front of anal fin; base of ventrals midw'ay between front of anal fin 
and middle of mandible. 
