FISHES FROM BERING SEA AND KAMCHATKA. 



37 



pectoral 32.5; length of ventral 14; length of caudal 21; chord of arch of lateral line 47. Dorsal ix, 28; 

 anal 23; pectoral 16; ventral i, 3. Plates in lateral line 47. 



Head and body compressed, deeper than wide; head narrow above, the sides nearly vertical; 

 supraocular rim much elevated, forming a narrow deep interocular groove; interorbital width 1.8 in 

 orbit; occiput flattened, without spines or ridges; snout blunt, the anterior profile steep; mouth small, 

 slightly oblique, the maxillary reaching vertical from front of orbit; jaws equal; teeth bluntly conic, 

 in wide bands on the jaws, the vomer and the anterior half of the palatines; preopercle with 4 short 

 simple spines; upper spine with strongly striate base, strong, sharp, directed backward and upward, 

 straight or with a scarcely perceptible upward curve; second spine shorter, directed vertically down- 

 ward; third and fourth spines concealed beneath the integument, directed downward and fonvard; 

 nasal spines strong. A pair of large supraocular flaps, with narrowly fringed margins, their length 

 equaling the distance between the middle of their bases; a pair of cleft flaps at middle of sides of 

 occiput, and a similar pair more widely separated at the posterior edge of occiput; a delicate nasal 

 filament, two filaments at anterior margin of preorbital, one near tip of maxillar>% one on the suborbital 

 stay, a divided filament near the angle of the opcrcle, a series along the edge of the preopercle, and a 

 few scattered filaments on the plates of the lateral line; both nostrils in short tubes. 



Fig. I. — Arcfiaulus biseriatus, new spcdcs. Type. 



Anterior half of the lateral line forming a low flat-topped arch, which rises obliquely toward the 

 head; plates along the lateral line 47, greatly diminishing in size posteriorly, but their upper edges 

 free and finely spinous throughout the series; two rows of similar plates along base of dorsals, smaller 

 but more strongly spinous than those of lateral line; the lower series contains 80 to 84 scales, counting 

 forward to the head, and extends on back of caudal peduncle but not to base of fin; its scales are 

 higher than long, attached at lower edge, the free margin sharply convex, the axis of scale directed 

 upward and slightly backward; the upper series consists of much smaller rounded scales, the free 

 spinous margin directed more posteriori)-, but not downward as in Icelinus, the series ceasing under 

 last rays of dorsal fin, the scales 84 to 88 in number, counting for\vard to head; these two rows of plates 

 are closely apposed and form a narrow band which becomes abruptly widened under anterior part of 

 spinous dorsal, where it covers the entire area between the spinous dorsal and the lateral line and 

 extends around the front of the dorsal fin to join its fellow of the opposite side, and invests the 

 entire width of the nape; a well-defined patch of small scales immediately behind the lower half of 



