REPORT ON THE DEEP-SEA FISHES. 199 



NannobracMum, n. gen. 



Head and body rather elongate and compressed, covered with deciduous scales of 

 rather large size. Cleft of the mouth very wide ; maxillary well developed, not dilated 

 behind. Teeth minute, in narrow bands, in the jaws, on the vomer, the palatine bones, 

 and the tongue. Eye rather small. Pectoral fins rudimentary ; ventral fins well 

 developed, eight-rayed, inserted at some distance behind the pectorals ; dorsal fin in the 

 middle of the length of the body with fourteen rays, its origin being between the ventrals 

 and the anal ; adipose fin small ; anal of moderate length ; caudal forked. Gdl-opening 

 very wide ; pseudobranchise small. Series of phosphorescent organs along the lower side 

 of the head, body and tail ; a gland-like luminous organ on the upper and lower sides of 

 the caudal peduncle. 



Habitat. — Indian Ocean. 



NannobracMum nigrum, n. sp. (PI. LII. fig. B). 



D. 14. A. 19. L lat. ca. 34. 



The single specimen in the collection has sufi"ered much at the time of capture and 

 has lost a great portion of its integuments. 



This fish is closely allied to Scopelus, and bears in its physiognomy and general form 

 of body a great resemblance to Scopelus engraulis. The depth of the body is contained 

 five and a half times in the total length, without caudal, the length of the head three 

 times and two-thirds. A great portion of the skuU is cartilaginous, the superficial bones 

 Ijeing extremely thin and modified for the reception of the wide muciferous cavities. 

 The eye is rather small, about one-fifth of the length of the head and equal to that of 

 the snout. Mouth extremely wide, rather oblique, with the lower jaw somewhat 

 projecting, extending backwards to the end of the prseoperculum. Intermaxillary as 

 long as maxillary, toothed throughout its whole length, both bones being very narrow and 

 rod-shaped. Hind margin of the prasoperculum very oblique. 



Gill-lamina very short; gill-rakers long, needle-shaped, eighteen on the outer 

 branchial arch, the longest as long as the eye. 



The origin of the dorsal fin is nearer to the extremity of the snout than to the root 

 of the caudal, and its last ray opposite to the eighth of the anal fin. Adipose fin narrow, 

 opposite to the end of the anal. The origin of the anal is opposite to the eighth ray 

 of the dorsal fin. Caudal emarginate. 



The pectoral fin is reduced to three or four small and extremely delicate filaments. 



The ventral fin is inserted consipcuously in front of the dorsal and extends backwards 

 to the vent. 



