104 NORTHERN ZOOLOGY. 



valve shells, none of them crushed, the shells passing entire, per anum, after their 

 inhabitants have been digested. 



DESCRIPTION 

 Of a specimen taken on the Labrador coast and preserved in rum. 



Form — much depressed, the head very wide posteriorly from the spreading of the sub- 

 opercular bones. The body tapers gradually from behind the pectorals to the caudal fin, 

 becoming at the same time less and less depressed, the extremity of the tail at the insertion of 

 the caudal fin being decidedly compressed. The gill-openings are about midway between 

 the snout and end of the tail, and the anus is halfway between the pectorals and anal fin, or 

 very little posterior to the gill -openings. The head (excluding the gill-plates), or rather the 

 cranium, which is slightly moveable on the spinal column, is not at all disproportioned to the 

 size of the fish ; it has a cubical form, and the large eyes, having a perfectly lateral aspect, 

 occupy the anterior halves of its sides. The upper surface of the cranium is flat, slightly hol- 

 lowed between the orbits, where it is narrower, becomes again wider before them, and arching 

 a little in a longitudinal direction, terminates abruptly and evenly, being supported on each 

 side by a vertical pillar that forms the anterior margin of the orbit. On the edge of the 

 forehead, between the tops of these pillars, there is a rounded knob about the size of a grain 

 of duck-shot, coarsely granulated like the rest of the skin, and very unlike the tapering, acute 

 snouts of M. vesjjertilio, nasuta, or even stellata. Beneath the knob-like snout, and between 

 the shafts of the pillars above mentioned, there is a deep circular cavity, which is lined by a 

 whitish membrane. A canal capable of receiving a crow-quill passes from the bottom of the 

 cavity between the orbits to the back part of the cranium. From under the orifice of the 

 canal there proceeds a long barbel, composed of a bony ray with a thickened tip and a coating 

 of soft skin : it is apparently capable of being protruded from the cavity, or retracted within 

 it, at the pleasure of the fish. The nostrils open by two small orifices before the base of each 

 of the orbital pillars. The mouth is situated directly under the anterior margin of the fore- 

 head when it is closed, and from the lower jaw inclining upwards the commissure of the lips 

 has then a crescentic form; but when the mouth is open the descent of the lower jaw causes 

 the intermaxillaries to advance on their pedicles, so that its orifice, which is then circular and 

 about equal in diameter to one of the orbits, is protruded beyond the snout. The labials lie 

 in the membrane behind the intermaxillaries. 



Teeth — like very fine shorn velvet, cover the opposing surfaces of the intermaxillaries and 

 lower jaw, the whole upper surface of the tongue, a broad rectangular plate on the vomer, a 

 smaller contiguous plate on each palate bone, and four convex plates on the upper side of the 

 gullet — the pharyngeal teeth being rather coarser than the others. 



Gill-covers. — The very thick, nearly semicylindrical suboperculum extends from the cheek 

 to the middle of the arm that supports the pectoral fin, rendering that part of the fish 

 much wider than the body. The thin, flat, nearly horizontal operculum, fills part of the space 

 between the suboperculum and the spine. The gill-opening is a small round hole, situated 

 between the arm of the pectoral and the spine, and opposite to the extremity of the suboper- 

 culum. 



