642 
BULLETIN OF THE UNITED STATES FISH COMMISSION 
Hoplichthys platophrys, new species. Fig. 250. 
Type, a specimen 70 mm. long, from station 3952, near Laysan Island, depth 351 fathoms; type, 
No. 51620, U. S. Nat. Mus. 
Differing from other known species of Hoplichthys in the small eye, wide interorbital space, the 
more complete union by membrane of the modified lower pectoral rays, and the weaker spines on 
head and lateral plates. 
Head 37 hundredths of total length Avithout caudal; greatest width of head, at base of spine- 
bearing ridges 28; diameter of eye 7; interorbital width 5; length of snout 13; length of maxillary 15. 
D. vi-15; A. 18; P. 13+3; V. i, 5. Plates 27. 
Snout somewhat broader and more squarely truncate than in II. citrinus ; eye very small; inter- 
orbital space much wider. The general spination of head agrees with H. citrinus, but the type is too 
young for a determination of details; spines along suborbital ridge, as well as those elsewhere on head, 
smaller than in citrinus, and not forming expanded lobes as in that species; mouth similar, with lower 
jaAV shorter, the maxillary reaching a little past front of orbit; teeth very minute, but distinguishable 
in very narrow bands on jaws, vomer and palatines; branchiostegals 7. 
The structure of the fins is wholly like that of II. citrinus, except that the lower 3 pectoral rays 
are joined by membrane to one another and to the rest of the fin for more than half the length of 
the rays. In our smallest citrinus, 96 mm. long, there is no approach to this condition. 
The plates agree in number and structure with the other species of the genus. There is a strong 
spine at the angle of each plate, with a small concealed one below and in front; the upper half of each 
plate contains a single denticulate ridge running downward and backward, the lowermost tooth on the 
ridge longer than the others. Young citrinus have also a single spinous ridge on upper half of each 
plate, the number of ridges increasing with age. 
Color in spirits, light olive, without white or silvery pigment; 3 broad and 2 narrow bars on back, 
as in young of citrinus and in adults of langsdorfii. In platophrys, the bars below soft dorsal end each 
in a black blotch, below lateral plates. Head with some dusky markings above, and 3 small black 
spots below suborbital ridge; pectoral with dusky mottlings; spinous dorsal with a broad black bar 
occupying all but base of anterior rays, and a narrow white margin; soft dorsal Avith a dusky spot near 
base of each ray, and a dusky subterminal band; anal with a wide black submarginal band, edged 
with white; caudal with a dusky terminal band. 
Only the type known. 
Family PTEROPSARID^. 
Osurus schauinslandi (Steindachner). 
Several specimens, mostly immature, were dredged in depths of 14 to 90 fathoms* Young speci- 
mens are more uniformly colored than adults, have the caudal emarginate but not deeply forked and 
the lobes not produced; the ventral fins are greatly produced, much longer than in adults, reaching 
base of fourth or fifth anal ray. In adults, the ventrals fail to reach origin of anal. 
