134 



The opercle is conspicuously expanded below and behind, and the branchio- 

 steo-al rays and membrane extend a considerable distance behind its edge, giving 

 the appearance of a broad fringe. 



The integument is invested with small strong scales, which on the blind side 

 and anterior half of the coloured side are cycloid, and on the posterior half of 

 the coloured side sharply ctenoid. Three lateral lines on the left side, the middle 

 separated from the upper by 16 or 17, and from the lower by 22 to 24 rows of 

 scales at the respective points of greatest divergence : none on the right. Those 

 on the left side are connected by an irregular cross line on the head. 



The longest rays of the dorsal and anal fins are about equal to the snout. 

 The ventral fin is almost indistinguishably confluent with the anal. 



Colours in spirit : warm brown, the opercles and caudal blackish : right side 

 colourless. 



Length 6 to 8 inches. 



Bay of Bengal, 68, 98 to 102, and 107 fathoms : Arabian Sea, off Malabar 

 coast, 100 fathoms. 



Regd. Nos. 12433, 12434, 12726 a to g, 12727 a to h, 12728 a to h, 13589- 



-i o'ni 647-659 



13o94, j- . 



Sub-order Physostomi. 



Family Ster iiopty chidce. 



Eight species of this family, belonging to six genera, are now known to 

 inhabit the seas of India. They probably all belong to the " Necton," though 

 they probably live below the depths to which daylight penetrates. 



Body naked, or with very thin and deciduous scales. Barbels none. 

 Margin of the upper jaw formed by the maxilla and premaxilla, both of 

 which are toothed. Gill-opening very wide, the opercular apparatus not 

 always completely developed. Pseudobranchiae present or absent. Air- 

 bladder simple, if present. Adipose fin present, but generally small. 

 Series of phosphorescent bodies along the ventral aspect of the body. 



Synopsis of the Indian Genera of the family Sternoptychidae. 



' I. Body short and elevated, its height more than half its length without 

 the caudal. Pseudobranehioe present : — 



1. Dorsal fin preceded by a large triangular transparent osseous 

 plate : no teeth on the vomer : — 



i. Body hatchet shaped ... ... ... Augyuopelecis. 



ii. The ventral constriction between the body and the tail is 

 filled by a curious transparent fold of skiu supported by 

 long interhsenial rays ... ... ••• Sfernoptyx. 



2. Dorsal fin preceded by a forked spine : teeth on the vomer ... Polyipnos. 



CO 



