474 Bulletin 47, United States National Museum. 



awl-shaped, rough iuteriorly. Brauchiostegals 10. Pyloric co^ca in great 

 number. Dorsal fin moderate, over ventrals ; anal rather long; caudal 

 forked. Scales moderate. Coloration silvery. Migratory fishes of large 

 size, inhabiting the streams of Arctic America and Asia; intermediate 

 between the Whitefish and the Trout, ((rrfvor, narrow ; h&ovq^ tooth.) 



772. STEIVODUS MACKENZII (Richardson). 

 (Inconnu.) 



Head 4| ; eye 6. D. 12 ; A. 14 ; scales 100. Eye less than snout, 

 nearly e(iualing the narrow iuterorbital width. Maxillary reaching a 

 vertical behind pupil, its length very slightly more than \ head. Supple- 

 mental bone long and narrow, nearly as wide as the maxillary, the ante- 

 rior end notched, the angle above the notch sharply pointed, the lower 

 angle bluntly rounded. Teeth all weak and flexible, bristle-like ; present 

 in a narrow band in upper jaw, the band extending laterally onto prox- 

 imal fifth of maxillary ; a similar narrow baud anteriorly in lower jaw ; 

 very broad patches of similar, but slightly stiff'er, teeth are present on 

 tongue, vomer, and jialatines. Gill rakers 7 + 17, the one in the angle 

 reckoned with the vertical limb, very stift' and bony, the longest * diam- 

 eter of eye ; they bear in their margins two rows of very short, weak 

 teeth, which do not make them appreciably rough. 



Here described from a specimen 32 inches long, from the delta of the 

 Mackenzie River, collected by Miss Elizabeth Taylor. Mackenzie River 

 and its tributaries below the cascades ; locally abundant and reaching a 

 large size, usually 5 to 15 pounds, but sometimes 30 to 40 pounds. A fair 

 food-fish, but the flesh is oily.* (Named for its discoverer. Alexander 

 Mackenzie, for whom the river was also named.) 



Salmo inackenzii, Kichardson, Franklin's Journ., 1823, 707, Mackenzie River. 



i«CM)(mHa TOrtcA-en^ii, GiiNTiiER, Cat., VI, 164, 1866. • 



Stenodus mackeiizii, Jordan & Gilbert, Synopsis, 304, 1883. 



234. ONCORHYNCHUS. Suckley. 

 (QuiNNAT Salmon.) 



Oncorhynchm, Sucki.ey, Ann. Xyc. Nat. Hist. N. T., 1861, 312, (ncnuleri). 

 Bjipsifario, GlLL, Proc. Ac. Nat. Sci. Phila., 1862, 330, {Jcennerh/i). 



Body elongate, subfusiform, or compressed. Mouth wide, the maxil- 

 lary long, lanceolate, usually extending beyond the eye; jaws with 

 moderate teeth, which become in the adult male enormously enlarged 

 in front. Vomer long and narrow, flat, with a series of teeth both on 

 the head and the shaft, the latter series comparatively short and weak ; 

 palatines with a series of teeth ; tongue with a marginal series on each 

 side ; teeth on vomer and tongue often lost with age ; no teeth on the 

 hyoid bone. Brauchiostegals more or less increased in number. Scales 

 moderate or small. Dorsal fin moderate ; anal fin comparatively elongate, 



♦According to Dr. Bean our species may be not distinct from the Siberian species, Stenodus 

 leucichthijs (Guldenstadt). 



