SUCKLEY MONOGRAPH OF THE GENUS SALMO. 151 



38. SALMO NAjMAYCUSII, Pennant. 



MACKINAW TROUT ; GREAT LAKE TROUT. 



Syx. — The Xummiaish salmon, Pexxaxt, Arct. ZooI. SnppL, ii. p. l:')9, 1792. 



iSahno ametltyHtas, Mitchill, Journ. Acad. Sc. Phil., vol. i, p. 410 ; De- 

 Kay, Nat. Hist. State of N. Y., Fishes, p. 240, PI. Ixxvi ;— Stouku, 

 Syiiop. 1846, p. 19.3. 

 Sahno narmnjcioih, EiCH, F. B. A., vol. 3, p. 179, PI. 79 aud 85 ; — KiRT- 

 LAXO, Eeport on the Zool. of Ohio, p. 19.5. — Boston Jonvii. N. Hist., 

 1842, iv, p. 25, PI. 3, fig. 2 ;— Agassiz, L. Superior, p. 331, Bost. 1850. 

 Salar namaycush, Valexciex'xes, Cuv. & Val., H. N. Poissoiis, sxi, p. 

 348, 1848. 



Sp. Cm. — I Drawn up from DeKay's description and the examination of 

 specimens in the Smithsonian Institution collection.] Body robust ; 

 dorsal outline moderately arched. Lateral line nearly straight. Scales 

 small, oval, adherent. Head one-fourth of total length. Nostrils double ; 

 contiguous muzzle somewhat pointed. Mouth large. Jaws strong ? in the 

 male, (when worn oat;) the upper are longest, the lower having a conical 

 l)oint at their tip ; jaws and tongue with a single row of teeth on each 

 side; vomer with but a single row. Teeth strong, sharj), translucent; 

 in the breeding- season showing a beautiful amethystine color at their 

 bases. Dorsal fin nearly in centre of fish ; its height slightly longer than 

 base. 



Eays.—Br. 12: D. 12-14: P. 15: Y. 9-10: A. 11-13. Pectorals low 

 down, pointed. Caudal strongly forked. Length from 2 to 5 feet. 



Colors. — Dark or dusky brownish-gray above: chin and under parts 

 light-ash or cream-color. Back and sides specked with numerous irregu- 

 larly-shaped spots of lig'liter gray, brown, or soiled -white. Lower fins 

 slightly yellowish. 



Diagnosis. — From S. siskoicet^ by its pointed snout and chin; by its 

 more deeply-forked tail; by the difference in the style or pattern of its 

 markings ; its larger size and larger head, which in this species is con- 

 tained foiu^ times in the total length, while that of the siskowet nearly 

 five. In the specimens examined by the writer, the teeth of the namay- 

 cush appear to rake backward more. From all other lake-trout it may 

 be distinguished by its great size. 



Hab. — Lake Huron, Lake Michigan, Lake Superior, and, according to 

 Richardson, all the great lakes which lie between the United States and 

 the Arctic Sea ; but never found in tidal waters. 



Only two specimens* of this fish are contained in the Smithsonian col- 

 lection — both young, the largest about 20 inches long. These possessed 

 a few teeth in a cluster at the anterior extremity of the vomer, and then 

 a few scattered in a single row along its shaft, for half its length. But 

 a single row of labial teeth. Sir John Richardson mentions a double 



* Full collections at date of puhlicatiou. 



