620 CONTEIBUTIOXS TO NORTH AMERICxVN ICHTHYOLOGY — IV. 



332.— ICOSTEfJS Lockington. 

 (Lockiugt'on, Proc. U. S. Nat. Mns. ii, 63, 18S0: type Icostcm wnigmaticus Lockington.) 



Body oblong, much compressed tbrou<ihout, the head thicker than 

 an}" part of the body. Dorsal outline rising rapidly to the origin of the 

 dorsal fin, thence more regularly curved; the region at the base of the 

 dorsal and anal strongly compressed; caudal peduncle slender, widened 

 at the base of tlu-tiu. JMouth large, horizontal; maxillary narrow, 

 reaching to beyond middle of eye. Teeth in jaws in one row, slender, 

 sharp, closely and regularly set, those in the lower jaw largest; no teeth 

 on vomer, palatines, or pharyngeals. Gill-rakers flexible, few; gill-mem- 

 branes separate, free from the isthmus. Branchiostegals C. Pseudo- 

 branchiie well developed. Lateral line conspicuous, continuous, do- 

 curved, groups of small spines present along its entire length. jSTo 

 scales anywhere on body or fins. Fins rough, with small spiuules; a 

 series along each ray, dividing as the ray branches; dorsal fin com- 

 mencing above the axil of the pectoral, composed of 50-00 rays, which 

 are all soft and flexible, some of the anterior unbranched; the fin low 

 in front, increasing in height behind; none of the rays more than once 

 forked; anal shorter than the dorsal, similar to it, of 35-40 rays; some 

 of the anterior apparently undivided; caudal fin elongate, fan-shaped, 

 the middle rays ])rodaced; accessory rays numerous, procurrent; pec- 

 torals with a fleshy base, fan-shaped, the nnddle rays longest; ventrals 

 thoracic, inserted just beliiud the pectorals, narrow, consisting of 1 

 short subspinous ray and 4 long soft rays. Air-bladder large. Ver- 

 tebra} numerous, the vertebral column extremely flexible and soft. 

 Cranial bones tolerably firm ; bones of the face and opercles very flex- 

 ible. Deep-sea fishes, from the Pacific, (sjzw, to yield, submit; (XTreoy, 

 bone — the "entire body being characterized by a want of firmness, as 

 it can be doubled up as readily as a piece of soft, thick rag.") 



9<S.'). I. seiaigssiaSicaas Lockington. 



Pellucid yellowish or brownish, with puri)lish spots and blotches of 

 irregular Ibrm ; the spots largest above, most numerous along the lat- 

 eral line; fleshy bases of caudal and pectorals spotted; throat and gill- 

 membranes with dark punctulations; fins dusky, obscurelj' blotched. 

 Longest ray of dorsal nearly reaching base of middle caudal i ays. Eye 

 in head, scarcely half the length of the snout or the width of the in- 

 terorbital space; diameter of caudal peduncle about 51 in greatest 

 depth. Head 4; depth 3. D. 52-55; A. 37-40; V. 1, 4; Lat. 1. 110-lL'O 



