1894.] A. Alcock — Becent Collection of Bathyhial Fishes. ] 35 



The depressed and sharply pointed snout is a little more than 

 one-third of the head in length and nearly four times the major dia- 

 meter of the eye : its macous pores, like those of the mandible and of 

 the rest of the head, are large slits : the anterior nostril is a large 

 sub-tubular slit situated on the lip close to the tip of the snout, the 

 posterior is a wide elliptical foramen situated, almost superiorly, partly 

 in the posterior and partly in the middle third of the snout. The 

 mouth-cleft is wide, extending an eye length behind the posterior 

 border of the orbit, or more than half way along the head, and the 

 maxillee are most remarkably massive. The teeth are in broad crowd- 

 ed bands, acicular or caniniform, and for the most part depressible : 

 those in the upper jaw are in two bands — an outer very broad-band of 

 large depressible teeth in four series which increase in size from with- 

 out inwards, and an inner narrow-band or very close-set row of small 

 rigid teeth — the two bands being separated throughout their whole 

 extent by a broad groove : the pre-maxillary teeth, which are much 

 enlarged, are in a broad patch standing outside the closed mouth : the 

 mandibular teeth are in at least five series increasing in size from 

 without inwards, and at the symphysis, where they are greatly enlarg- 

 ed, they form a patch which fits into a wide notch in the upper jaw : 

 the vomerine teeth form a short row of fangs. Tongue small and inti- 

 mately adherent throughout to the floor of the mouth. Skin scaleless, 

 glandular. Lateral line formed by a row of large brilliant close-set 

 pores. Grill-openings wide, crescentic, separated by a very narrow 

 interspace. 



Vertical fins well developed, the dorsal beginning just in advance 

 of the gill-opening. Pectorals narrow, pointed, more than half the 

 snout in length. 



The stomach is large, extending the whole length of the abdominal 

 cavity, and is very distensible : the intestine in its posterior portion is 

 coiled in a series of close pleats : only the left lobe of the liver is deve- 

 loped : pancreas large : a large air-bladder extending behind the vent. 



Colour : body and fins blue-black ; pectorals with narrow whitish 

 edge and tip : margin of gill-opening and of all the mucous pores of 

 the head and lateral line brilliant white. 



A mature female between 25 and 26 inches long. 

 Loc. Laecadive Sea, Station 150; 719 fathoms. 



This species appears to differ from Xenomystax atrarius, dredged 

 by the U. S. Fish Commission in 401 fathoms off the coast of Ecuador, 

 only in the greater relative length of the tail, the nearer approximation 

 of the gill-openings, and the greater length of the pectoral fins. 



