474 Bulletin 47, United States National Museum. 



awl-shaped, rough interiorly. Brarichiostegals 10. Pyloric coeca 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, (arevb^, narrow ; odovf, tooth.) 



772. STENODUS MACKENZII (Richardson). 



(INCONNU.) 



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

 nearly equaling the narrow interorbital width. Maxillary reaching a 

 vertical behind pupil, its length very slightly more than i 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 band anteriorly in lower jaw ; 

 very broad patches of similar, but slightly stiffer, teeth are present on 

 tongue, vomer, and palatines. Gill rakers 7 -f- 17, the one in the angle 

 reckoned with the vertical limb, very stiff and bony, the longest f 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 mackenzii, RICHARDSON, Franklin's Journ., 1823, 707, Mackenzie River. 

 Luciolrulta mackenzii, GUNTHER, Cat., vi, 164, 1866. 

 Stenodus mackenzii, JORDAN & GILBERT, Synopsis, 304, 1883. 



234. ONCORHYNCHUS, Suckley. 

 (QUINNAT SALMON.) 



Oncorhynchus, SUCKLEY, Ann. Lye. Nat. Hist. N. Y., 1861, 312, (seouleri). 

 Hypsifario, GILL, Proc. Ac. Nat. Sci. Phila., 1862, 330, (tennerlyi). 



Body elongate, subfusiforin, 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. Branchiostegals 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 

 leudchthys (Guldenstadt). 



