SALMONIDA. — XXXIV. 79 
sides white; centre of each scale silvery; outside dotted, the 
sides thus with faint pale stripes. Head 4; depth 3. D. 11. 
A. 11. Scales 8-74-7. L. 18. Great Lakes, N., scarce. (An 
Indian name.) 
81. THYMALLUS Cuvier. (@vpadXos, ancient name of the 
Grayling.) 
189. T. signifer Richardson. AMERICAN GRAYLING. Body 
compressed, rather elongate; head short, subconic; mouth moder- 
ate, the maxillary to middle of eye; jaws subequal; teeth on tongue 
disappearing with age; eye large, 3 in head; a bare space on 
breast ; gill rakers slender, X + 11; D. very high, especially in 
males, highest in specimens from far North. Purplish gray, with 
small black spots; ventrals dusky, with pale lines; dorsal highly 
variegated, with crimson and dusky streaks and greenish and rose- 
colored spots. Head 43; depth 42. D. 20. A. 10. Scales 8-90 
to 100-9. L. 18. Arctic America, in clear, cold streams. The 
Michigan Grayling is var. ontariensis Cuv. & Val. (=T7’. tricolor, 
Cope), with rather longer head and lower dorsal, its height rarely 
greater than depth of body; in a few streams in N. Mich. and Mon- 
tana; a remnant perhaps of the glacial fauna. (Lat., bearing a 
banner. ) 
82. SALMO (Artedi) Linneus. (Lat., salmon, originally from 
salio, to leap.) 
(Besides the native Salmon, the following species have been 
introduced into waters within our limits: Salmo fario L., the 
“ Brook-trout,” or “ Brown Trout,” of Europe, with the vomerine 
teeth well developed and the scales rather large, about 120. Salmo 
gairdnerit Richardson, the “Rainbow Trout ” of California, similar 
to the last, and with about 130 scales. Salmo mykiss Walbaum, 
the Red-throated or Rocky Mountain Trout, with larger mouth 
and the scales about 175. Besides this, the great Salmon of the 
Columbia, the Quinnat or King Salmon, Oncorhynchus tschawytscha 
(Walbaum), has been introduced. ‘This, the most valuable of all 
Salmonide, may be known by the presence of 16 anal rays, and by 
the black spots on back and upper fins. Its scales are about 145.) 
a. Marine Salmon, anadromous, with the vomerine teeth little developed, 
those on the shaft of the bone few and deciduous; scales large (lat. 1. 
120); C. deeply lunate, truncate in old age; no hyoid teeth; sexual 
differences strong; breeding males with the lower jaw hooked upwards, 
the upper emarginate or perforate, to receive its tip (Salmo). 
190. S. salar Linneus. Common Satmon. Mouth moderate, 
maxillary reaching past eye, 24 to 3 in head ; preopercle with a 
distinct lower limb. Brownish above, the sides silvery; many black 
spots on head, body and fins, these sometimes X-shaped; sides with 
