1914 Bulletin 47, United States National Museum. 



2292. ICELUS SPINIGER, Gilbert. 



Head ,2i to 3; depth 5; eye 3 to 3 in head. D. IX, 20; A. 17; P. 18; V. 

 I 3. Closely resembling Icelus Mcornis, but differing conspicuously in the 

 armature of the dorsal series of plates in the comparatively plane occiput, 

 and in other characters. Caudal peduncle very slender, its depth 2 in 

 orbit; mouth large, the maxillary reaching slightly beyond middle of 

 orbit, its length -J- head ; teeth very finely villiform, present in rather wide 

 bands in jaws and on vomer and palatine bones; nasal spines strong, 

 separated by the high ascending processes of the premaxillaries ; inter- 

 orbital space very narrow, grooved, its width less than diameter of 

 pupil; orbital rirn becoming elevated anteriorly and posteriorly, and,-at 

 the latter point, strongly denticulated; behind the orbital region, the 

 occiput is shallowly concave, being bounded laterally by 2 low, evenly 

 rounded ridges, which become narrower posteriorly, and end each, in a 

 strong spine projecting backward in line with the series of dorsal prickles ; 

 preopercular spines similar to those of Icelus Mcornis, the uppermost, as in 

 the latter, occasionally simple instead of bifurcate; the second spine 

 usually directed straight backward, and the 2 following downward and 

 forward; gill membranes broadly united, free from the isthmus, and 

 neither pore nor slit behind the innermost gill; braiichiostegals 6; eye 

 large, longer than snout; a slender tentacle present over the posterior 

 part of each orbit; a series of plates from nape along each side of dorsals 

 to back of caudal peduncle, and a second series along lateral line, as in 

 Icelus bicornis; the dorsal series with 28 to 35 plates, each of which bears 

 at its center a single strong spine directed outward and backward. In 

 Icelus Ucornis, each plate is traversed by an oblique ridge, the margin of 

 which is denticulated, the central tooth being the strongest and cor- 

 responding to the single spine present in Icelus spiniyer. The latter agrees 

 with Icelus canaliculatus in having an inner series of dorsal plates alter- 

 nating with the principal series, each of the smaller plates bearing a 

 minute prickle, discernible with difficulty. The plates along the lateral 

 line, 41 to 44 in number, are similar to those in Icelus Ucornis, having their 

 upper and posterior free margins serrulate. A few scattered spinous 

 plates present in axillary region. Dorsal fins not connected, the spines 

 very slender and rather high; pectorals long, reaching front of anal; 

 ventrals not reaching vent. Color light olivaceous above, white below; 

 upper parts mottled with dark brown; back with 4 faint black cross bars, 

 the first under spinous dorsal, the second and third under soft dorsal, the 

 fourth at base of caudal ; a brown blotch on cheek, 1 on base of pectoral, 

 and an irregular series along full length of body just under the lateral 

 line; 2 prominent black blotches on first dorsal; the second dorsal, 

 caudal, and pectoral barred ; other fins unmarked ; mouth and gill cavity 

 white. Coast of Alaska; numerous specimens from Albatross Stations 

 3216, 3224, 3225, 3226, 3257, 3258, 3263, 3267, 3278, 3279, 3280, 3292, 3302, 3311, 

 3334, in 17 to 121 fathoms. These stations are located in the vicinity of 



