Jordan and Evermatm. Fishes of North America. 969 



ACROTIN.K: 



cc. Ventral fius wanting; caudal emarginate; lateral line without spinules; dorsal fin 

 very long, of about 50 rays. ACROTUS, 446, 



442. ICICHTHYS, Jordan & Gilbert. 



, JORTIAV & GILBERT, Proc. IT. S. Nat. Mus., 1880, 305, (lockingtom). 



Body elongate, not elevated, not compressed at the bases of the vertical 

 fins. Head moderate. Eyes lateral. Mouth terminal, little oblique, with 

 small, sharp teeth in one series, in the jaws only. Premaxillaries not 

 protractile. Gill membranes separate, free from the isthmus ; gill rakers 

 long. Pseudobranchiae present ; branchiostegals 7. Body covered with 

 small cycloid scales. Lateral line continuous, unarmed. Bases of fins 

 without spinules; dorsal and anal fins long and low, composed of 

 soft rays only; pectoral fins moderate, their bases fleshy, as in Icosteus'^ 

 ventral fins small, thoracic, I, 5. Caudal rounded. Pyloric cceca about, 

 6, large. Bones all very flexible, cartilaginous. Deep-sea fishes. (, 

 to yield or submit ; i0uf, fish; in allusion to the flexible skeleton.) 



1369. ICICHTHYS LOCKINGTONI, Jordan & Gilbert. 



Head 5 ; depth 4 ; eye large, lateral, longer than snout, 4 in head. D. 

 40 ; A. 28 ; scales 120. Body oblong, somewhat compressed, the caudal 

 peduncle rather slender, Head moderate, compressed, with vertical 

 cheeks, rather broad and slightly convex above, the snout abruptly 

 descending. Mouth moderate, little oblique, the slender maxillary 

 scarcely widened at the tip, extending to beyond front of pupil ; anterior 

 edge of premaxillary on level of lower rim of eye; lips thin; premaxil- 

 lary tapering backward, not forming the whole margin of upper jaw ; 

 maxillary behind slipping entirely under the membranous edge of preor- 

 bital ; preorbital rather wide with one or two series of rather large, thin, 

 cycloid scales ; lower jaw prominent, projecting in front, included at the 

 sides. Teeth in jaws only, minute, sharp, closely and evenly set, larger 

 and less numerous than in Icosteus fenirjmaticua. Cheeks rather wide ; 

 preopercle with a prominent crest, behind which are some radiating 

 mucous cavities; the bone with a broad, prolonged, flexible, membrana- 

 ceons edge, covered with radiating strisR,each of which ends in a flexible 

 point; opercle and subopercle rather large, extremely thin, and each 

 crossed by radiating striae. Branchiostegals 7. Gill rakers long, slender, 

 sharp, close-set, and moderately stiff, their length nearly f diameter of 

 eye. Scales very small, soft, and smooth, covering the body evenly, 

 but becoming smaller below ; lateral line nearly straight, apparently 

 continuous. Dorsal fin long and low, beginning nearly midway between 

 vent and base of ventrals; all the rays soft and articulated, and all 

 except the first branched ; first rays very low, the fin gradually rising 

 posteriorly, the highest rays 3 in head, somewhat scaly ; anal fin similar, 

 shorter, beginning slightly in front of the middle of the body and ending 



