148 Mr. A. Alcock on 



than to the base of the caudal. The long anal fin approaches 

 within less than half a head-length of the base of the caudal. 

 The pectorals are on almost the same plane as the ventrals, 

 and these arise about midway between the base of the former 

 and the origin of the anal. 



The luminous organs are in two series on either side, and 

 are of the " bull's-eye " type (a white ball in a black silver- 

 lined pocket) ; the upper row extends from the basihyal to 

 the base of the caudal tin, but the lower row extends only to 

 the beginning of the anal fin ; each of those of the upper row 

 is surmounted by a tiny accessory organ. In addition there 

 are some luminous organs on the head, notably one at the 

 anterior angle of either orbit, and the whole crown of the 

 head (from the snout to the occiput) appears to have been 

 luminous. 



Andaman Sea, 405 and 185 fath. 



The largest specimen is 5 inches long. 



Family AlepocephalicUe. 



Xenodermichthys, Giinther. 



Xenodermichthys squamilaterus, sp. n. 



B. 6. D. 20. A. 18. P. 6. V. 6. 



Body elongate, compressed, covered with jet-black skin in 

 which scattered granular luminous organs are embedded. The 

 lateral line is a salient tube which runs straight down the 

 middle of the body and is stiffened by thin subcutaneous 

 equidistant scales ; in each interspace between the scales is a 

 pore resembling a luminous organ. 



Head about 3|, greatest body-height about 5£ in the total 

 without the caudal. Snout about two thirds the length of 

 the eye and about equal to the width of the interorbital 

 space ; eye about a fourth the length of the head. Lower 

 jaw slightly prominent, with the symphysis acute. Mouth- 

 cleft wide, the maxilla nearly reaching to the level of the 

 posterior border of the orbit. A close-set row of extremely 

 minute teeth in either jaw only. 



Gill-openings wide, the membranes quite separate; four 

 gills, with long close-set gill-rakers ; pseudobranchise 

 present. 



The anal fin lies entirely in the posterior third of the body 

 (measured without the caudal), but the first few dorsal rays 

 are in advance of this. The ventrals are in the after half of 



