REPORT ON THE DEEP-SEA FISHES. 31 



of moderate length, obtuse, and with the jaws equal in front ; eye small, not quite 

 one-sixth of the length of the head, and two-thirds of that of the snout. Posterior 

 margin of the prseoperculum oblique, rounded. Operculum narrow, membranaceous. 

 Cleft of the mouth oblique, very wide, the maxillary reaching far behind the eye 

 to the mandibulary joint. It is obliquely dilated behind. Origin of the dorsal fin 

 but little nearer to the extremity of the snout than to the root of the caudal, and not 

 much in advance of the vent ; its last ray opposite to the last ray of the anal. Pectoral 

 with narrow base, rather small, scarcely extending to the origin of the dorsal. Ventral 

 very small, its root equidistant from the vent and the vertical from the base of the 

 pectoral ; the caudal rays extend a considerable distance forward on the upper as well as 

 lower side of the tail, and are enclosed within the remains of the embryonic vertical fin. 

 Gill-rakers of the first branchial arch twenty-seven in number, the longest nearly twice 

 as long as the eye. Transparent ; with the sides of the head and the abdomen black. 



Habitat. — Mid- Pacific, Station 271; depth, 2425 fathoms. One specimen, 3^ inches 

 long. 



Near the Low Archipelago, Station 276 ; depth, 2350 fathoms. One specimen, 

 3j inches long (in bad condition). 



The specimen which has served for the description is not in a good state of preserva- 

 tion ; in fact, the structure of the bones, integuments, and muscles of the fish is so soft 

 that wc can scarcely hojic ever to obtain a perfect animal. The rays of the vertical fins 

 are also much broken, so that it is impossible to distinguish in the dorsal fin between 

 spines and rays. The soft condition of the parts, the embryonic condition of the caudal, 

 the want of development of the ventral fins, the absence of colour, the short branchial 

 laminae, &c., indicate that this fish inhabits actually the great depth as recorded in the 

 journal of the Challenger. 



Stephanoheryx. 



Steplianoheryx, Gill, Proc' U.S. Nat. Mus., 1884, vol vL p. 258. 



This genus is very imperfectly known at present, and said to be closely allied to 

 Melam2>haes, but with cycloid scales which are armed about the centre with one or two 

 erect spines, and with only five soft rays in the ventral fin. 



Stephanoheryx mome (D. 14. A. 13. P. 10), is named from a single small 

 specimen, obtained by the United States S.S. " Albatross," in the Atlantic, lat. 

 41° 9' N., long. 65° 55', at a depth of 1253 fathoms. 



Beryx, Cuv. 



Body compressed and deep, covered with ctenoid scales which are regularly arranged ; 

 abdomen compressed, trenchant, but without enlarged dermal scutes. Head rather large. 



