203 
of the Bay of Bengal. 
Scales extremely deciduous ; the few that still adhere are 
small and membranous, and those of the lateral line, which 
are inch in their major diameter, have each a salient 
membranous tube. 
The dorsal and anal tins 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. Yentrals 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 caeca in an arborescent mass ; no air-bladder. Ver- 
tebrae 10/14. 
Colours in life, uniform bluish black, with an uneven silvery 
sheen. 
Total length 65 inches. 
Hab . Vide Station 96. Four specimens, all mature ovige- 
rous females. 
This fish appears to have many Nomeid affinities. 
Family Trachinidae. 
Ponerodon, 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 ; pseudobranchiae. Lateral line single, uninter- 
rupted. Abdominal cavity enormous. No air-bladder. No 
pyloric caeca. No anal papilla. Vertebrae 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 
in the total without the caudal. 
Head low, long, and compressed, its length being 3£ in the 
