CLUPEOIDEvE. 233 



with the Hiodon clodalis of the Ohio, described by M. Le Sueur ; but a more care- 

 ful consideration of his figure and description has induced me to give a distinct 

 specific name to the northern fish *. 



The Naccaysh is taken during the summer months only, and iu small numbers, 

 in the gill-nets set for other fish. It bites eagerly at an artificial fly or worm, but 

 angling is seldom practised in the fur countries. Its flesh is white, resembling 

 that of the perch in flavour, and excelling it in richness. The want of an adipose 

 fin separates the Naccaysh from the Salmonoidese, with which it seems, in some 

 respects, to have a greater affinity than with the Clupeoideee : it differs from both 

 in having only one csecum. 



DESCRIPTION 



Of the recent fish taken at Cumberland House, lat. 54° N., May, 18'20. 



Form. — Profile sub-oval, the belly more curved than the back ; tail much narrower than 

 the body, its under margin joining the curve of the belly by a considerable slope which is 

 occupied by the anal fin. Body greatly compressed ; thickest, above the lateral line, and thin- 

 ning gradually into the very acute even edge of the belly : the back thins off more suddenly, 

 but its ridge is less sharp than the rim of the belly. The head likewise is much compressed 

 and has a conical profile, the snout forming an obtuse apex. The vertex is covered with 

 smooth skin, and there is a large scale on each side of the nape. The large eye approaches 

 very close to the margin of the mouth. The nostrils are placed above the level of the eye in 

 the triangular space between the orbit and tip of the snout : the membranous border of the 

 anterior opening forms a lid to the posterior one. The whole cheek is covered by the nearly 

 circular plate of the infra-orbit ar bones. Gill-openings large ; gill-plate edged by a narrow, 

 somewhat cartilaginous border. The mouth has a wide orifice which descends obliquely as it 



* The following is M. Le Sueur's character of the genus : — 



" Char. Body as in the genus C/upea, hut without the carinated abdomen. Tongue supplied by the os hyoides, which 

 is furnished with strong teeth. One dorsal fin. Eyes very large." — " Body compressed as in the herrings, but without 

 abdominal serratures. Head narrow; snout very short, obtuse, without scales; posterior sub-urbits covering the cheeks, 

 anterior ones concealing the maxillaries ; preoperculum large, triangular, curving under the throat, its posterior an«-le 

 rounded, covering almost the whole of the subopercnlum ; the interoperculum very small, squamiform ; operculum large, 

 rounded, having a notch in its upper part. Eyes very large, situated near the end of the snout, and nearly occupying the 

 space between the summit of the head and the angle of the mouth ; they are furnished with a gelatinous, nictitating mem- 

 brane, which extends on a part of the operculum. Nostrils double, placed at the end of the snout, above and near the 

 intermaxillaries. Mouth of a middling size, jaws sub-equal ; intermaxillaries short, articulated with the maxillaries, both 

 very narrow. Teeth conic, equal, close set, in a single row on the maxillaries and intermaxillaries ; stronger and in several 

 rows on the lower jaw ; very fine on the palate; the vomer equally furnished with several ranges of very strong ones on its 

 whole length. Tongue supplied by the os hyoides, which is armed with two principal rows of very strong, bent, conic teeth, 

 between which there are several rows of very small teeth. Branchiostegous rays short, superior ones enlarged at their 

 extremities, of the number of eight or nine ; branchial arch furnished on each side, anteriorly with denticulations (rakers^ 

 which interlock one with the other. Air-bladder long, compressed ; two small globular air-vessels placed each in a cavity 

 under and on each side otthe cavity of the cranium: these appear to enable the fish to rise with facility to the surface of 

 the water to take its prey. It was not ascertained whether they communicated with the bladder or not. Fins : a single 

 dorsal, placed opposite to the commencement of the anal ; pectoral placed low, near the opercula : ventrals midway between 

 the pectorals and anal. Scales large, pellucid at the edges, easily deciduous." Lb Sueur, /. c. 



2h 



