40 



V. S. S R. K. EXP. AND SURVEYS — ZOOLOGY GENERAL REPORT. 



List of specimens. 



Tribe of Cataphracti, or mailed cheeks. 



A feature common to all the "mailed cheeks " consists in the extension backwards of one, 

 and sometimes two, of the sub-orbital hones as far as the limb of the preopercle, thus con- 

 stituting a bridge, or else a bony buttress across the cheeks. 



We be<'in the series with the Heterolepid family, wliich, by its general aspect, reminds us of 

 the Trachinids of the percoid tribe, thus bringing the two groups in closer union. 



The family of Triglida, of exclusively marine habits, and which is composed of the gurnards, 

 sea-robins, and sea-swallows of the Atlantic coast, has furnished no representatives along the 

 Pacific coast. 



The cottoids, or sculpins, and bull-heads, on the other hand, seem to compensate for the 

 absence of the former in the fresh waters of the western slope of the Kocky mountains, and 

 especially in the sea. 



The scorpaenids, or sea scorpions, and rose fishes, exclusively marine also, are well represented, 

 particularly in species of the rose-fish genus, or Norway haddock. 



The gasterosteid, or sticklebacks, of the fresh and brackish waters are likewise quite 

 numerous. 



Family HETEHOLEPIDAE, Girard. 



The natural characters which may be assigned to this family, in order to distinguish it from 

 the other groups of Cataphracti, or mailed cheeks, consist in an elongated, sub-fusiform, and 

 rather compressed body, covered with small scales, varying in size, shape, and structure, being 

 either ctenoid or cycloid. The dorsal region is almost entirely occupied by a long and continuous 

 fin, or two distinct fins, more or less contiguous, composed of undivided rays in the former case, 

 of undivided and of articulated ones in the second. The anal fin is elongated, and, generally 

 speaking, resembles the soft portion of the dorsal, with the exception that the interradial 

 membrane is more or less emarginated. The ventral fins are situated under the pectorals. 



Canine teeth exist upon the jaws ; either canine, or velvet-like ones, or both kinds upon the 

 vomer and palatines. The head above is spineless, provided sometimes with membranous flaps, 

 like Scorpaena. The opercle and preopercle are either smooth or provided with small spines. 

 A bony arcade, formed by the suborbitals, may be traced across the cheek, concealed under the 

 flesh, .skin, and scales of that region, and which tells of the afiinities of this family with the 

 tribe of Cataphracti. 



