of the Bay of Bengal. 203 



Scales extremely deciduous ; the few that still adhere are 

 small and membranous, and those of the lateral line, which 

 are y^^ i^i^h in their major diameter, have each a salient 

 membranous tube. 



The dorsal and anal fins have thick gelatinous bases ; the 

 dorsal spines are short and rather weak, and their intercon- 

 necting membrane is delicate ; the anal spines are in close 

 contact with each other and with the rest of the fin. Caudal 

 symmetrically forked. Pectorals pointed, their length rather 

 more than four fifths the height of the body. Ventrals much 

 shorter than the pectorals ; they are adherent to the abdo- 

 men throughout their inner border, and can be retracted 

 within a shallow furrow in the middle abdominal line. 



Peritoneal cavity large, the membrane black ; numerous 

 pyloric cseca in an arborescent mass ; no air-bladder. Ver- 

 tebrse 10/14. 



Colours in life, uniform bluish black, with an uneven silvery 

 sheen. 



Total length Q\ inches. 



Hah. Vide Station 96. Four specimens, all mature ovige- 

 rous females. 



This fish appears to have many Nomeid affinities. 



Family Tracliinidse. 

 PONEEODON, gen. nov. 



Body elongate, naked. Eyes lateral. Two separate dorsal 

 fins, of which the second is much the longer, and equal, oppo- 

 site, and similar to the anal ; ventrals thoracic ; pectoral rays 

 branched. Cleft of mouth extremely wide ; jaws distensible 

 and armed with canine teeth, as are also the palatines. Gill- 

 openings very wide, the gill-membranes united anteriorly ; 

 preoperculum with a (small) spine at its angle ; seven bran- 

 chiostegals ; pseudobranchiai. Lateral line single, uninter- 

 rupted. Abdominal cavity enormous. No air-bladder. No 

 pyloric cffica. No anal papilla. Vertebrse 14/24. 



6. Ponerodon vastator, sp. n. (PI. IX. fig. 5.) 



Tissues fragile ; gape and abdomen enormously distensible. 



B. 7. D. 10/29. A. 29. P. 12. V. 1/5. 



Body somewhat elongate and compressed, its height being 

 4^ in the total without the caudal. 



Head low, long, and compressed, its length being 3^ in the 



