FISHES OF HAWAIIAN ISLANDS. 
609 
Famly STERNOPTYCHIDvE. 
Sternoptyx diaphana Hermann. 
Several small specimens were secured, presenting no very wide differences in form or general 
appearance. One individual differs from all the others in having the 2 frontal ridges converging 
strongly backward, thus inclosing a narrowly wedge-shaped space. In other cases these ridges are 
parallel, their terminal spines diverging. Specimens were taken at the following stations: Nos. 3888, 
off the north coast of Molokai, 809 fathoms; 3904, off north coast of Molokai, 295 fathoms; 3917, off the 
south coast of Oahu, 294-330 fathoms; 4005, near Kauai, 480-577 fathoms; 4026, near Kauai, 368-1021 
fathoms; 4105, Kaiwi Channel, 314-335 fathoms; 4110, Kaiwi Channel, 449-460 fathoms; 4111, Kaiwi 
Channel, 460-470 fathoms; 4154, near Bird Island, 636-850 fathoms; 4155, near Bird Island, 1164-1594 
fathoms; 4166, near Bird Island, 293-800 fathoms. 
Polyipnus nutting-i, new species. Plate 73. 
Type, 83 mm. long, from station 4088, in the approach to the Pailolo Channel between Molokai 
and Maui, depth 297 to 306 fathoms; type, No. 51599, U. S. Nat. Mus. 
Head 3.3 in length without caudal; depth 1.4; depth of caudal peduncle 8.5; horizontal diameter 
of eye 7.25; vertical diameter 6.25. D. 13; A. 17; P. 13; V. 7. 
Closely resembling in form P. spinosus Gunther, from the Philippines, and P. stereope Jordan and 
Starks, from Japan, but the posterior half of the body tapers more rapidly and forms a longer, slenderer 
caudal peduncle. The eye is larger, its horizontal diameter 2.2 in the head. The pair of crests on 
top of head are higher and very thin, provided with minute subequal spines equally spaced, the 
posterior 2 of these spines parallel to the others and not specialized. The post-temporals are movably 
articulated with the cranium, their proximal portions forming 2 slightly diverging ridges behind the 
occiput, each ridge minutely serrulate and terminating posteriorly in a backwardly directed spine, 
which is much shorter and weaker than in P. stereope. Through the lateral motion of the post-tem- 
porals, these spines can be approximated on the mid-dorsal line, or divaricated like the preopercular 
spines of cottoids. The distal limb of the post-temporal is directed downward and a little forward, its 
upper portion provided with a serrulate crest. There are no strong accessory spines directed down- 
ward and backward from the base of the post-temporal spine, but the serrations at the base of the spine 
are coarser than elsewhere. The pair of predorsal spines are weaker than in P. stereope, and the ridges 
converge less strongly forward. Both limbs of the preopercle are serrulate and the angle bears a claw- 
like spine hooked forward, this spine much smaller than in P. stereope. Cleft of mouth vertical, tip of 
mandible a little included; both maxillary and mandible very broad, the inferior mandibular margin 
serrulate, its angle with a strong triangular spine directed downward and forward; a broad supplemental 
maxillary bone present, with a smaller scale-like lamella overlying it proximally; premaxillary lying 
along anterior border of proximal six-tenths of maxillary; premaxillary teeth in a very narrow band or 
double series, the anterior row directed downward, the others hooked backward; the distal portion of 
maxillary, where it forms the border of the jaws, bears a similar single or double series of minute 
teeth; mandibular teeth in a slightly wider band at symphysis, in a single series laterally, those on 
vomer in 8 or 10 short longitudinal series, which slightly diverge backward; gill-membranes broadly 
united, free from isthmus; gill-rakers very long and slender, 7 (6 to 8) on vertical limb of outer arch, 
15 (14 to 16) on horizontal limb; rows of gill-laminae much longer than gill-arches; where continued 
above the latter, they are firmly attached along inner side of shoulder girdle; branchiostegals 9; pseudo- 
branchiae large. 
Front of dorsal fin midway between tip of snout and base of caudal; adipose dorsal low, the length 
of its base } to ■§ the distance between first dorsal fin and upper caudal rays; origin of anal fin vertically 
below middle of dorsal, the distance between its last ray and the middle of caudal base equaling the 
vertical diameter of eye; below and in advance of pectoral base a horizontal serrated ridge, forming the 
margin of a wing-like expansion of the coracoid; a downwardly directed spine marks the clavicular 
symphysis; the length of the narrow pectoral fin equals the distance from tip of snout to hinder edge 
of orbit. 
