of the Bay of Bengal. 22 1 



except at tlie extreme antcrii^r limit, its place being taken by 

 a long eluf^tic muscular band which extends from the tip of 

 the hvi'id to the inner surface of the mandibular symphysis ; 

 the n\outh-cleft and the gill-cleft being thus continuous 

 beneath almost divide the head from the rest of the body; 

 the lower jaw ])rojects beyond the upper. Teeth, everywhere 

 except in the maxilla, in the form of slender acute rigid 

 fangs; in each preniaxilla laterally eight or nine, with three 

 remote stouter ones at the symphysis; in each half of the 

 mandible laterally an uneven row of over twenty, ^vith five 

 (one median flanked on each side by a pair) of su])erior 

 size at the symphysis ; in each palatine a row of seven or 

 eight, increasing in size from before backwards, and a patch 

 on the upper pharyngeal bones ; maxillary teeth in the form 

 of even, close-set, recurved serrations, of which there are over 

 thirty in each bone. 



Gill-cleft extremely wide and oblique, its antero-supcrior 

 limit being above the middle of the eye ; gill-cover reduced 

 ajiparently to a narrow straight preoperculum, very obliquely 

 articulated, furnished with a narrow membranous fringe ; 

 four branchial arches, extremely weak and flexible, bearing 

 very narrow lamina ; gill-rakers rudimentary. 



Body scalelcss. Skin thick, soft, velvety, and uniformly 

 covered with adherent tenacious mucus ; apparently no lateral 

 line. Besides the large luminous glands already described, 

 there are two regular rows of minute luminous organs along 

 the ventral half of the body on each side ; the upper, num- 

 bering about fifty, extending from the gill-opening to the base 

 of the caudal ; the lower, numbering about forty, skirting the 

 ventral profile from the isthmus to the fifth anal ray; a few 

 similar luminous organs on the crown of the head. 



The dorsal fin begins slightly in advance of the posterior 

 fifth of the body, and is equal and opposite to the anal. The 

 longest (central) anal rays are a little longer than the corre- 

 sponding dorsal rays, and are equal to the depth of the tail 

 at their point of origin. The caudal is deeply forked, with 

 the lower lobe the broader and longer and about -g'^j of the 

 total length. 



Pectorals absent. The ventrals arise in the anterior half 

 of the body, their point of origin being 1^ times as far from 

 the vent as from the margin of the gill-cleft ; the two outer 

 rays are thickened, coherent throughout, and prolonged_, their 

 leno'th being two fifths of the total len2,-th includino: the 

 caudal ; the inner rays are short and weak. 



Stomach siphonal, its cul-de-sac extending halfway along 

 the abdominal cavity ; intestine straight, opening at the 



