4G. SALMONIDJ5 SALMO. 315 



than in the adult, as in all trout). Scales moderate, varying to rather 

 small. Back and caudal peduncle profusely covered with rounded 

 black spots of varying size; doisal, caudal, and adipose fin covered 

 with small spots about as large as the nostril; a few spots on the head; 

 belly rarely spotted ; inner edge of the mandibles below with a red 

 blotch; sea-run specimens are nearly uniform silvery; males with a 

 broad lateral band and patches or light red; extremely variable in color 

 and form. Head 4; depth 4. D. 10; A. 10. Creca 43. Scales variable 

 in size, 33-150-30 to 39-170-30. The common trout of the Eocky Mount- 

 ains and Cascade region, abounding in all the streams of Alaska, 

 Oregon, and Washington, where it descends to salt water, and reaches 

 a weight of 20 pounds (Columbia River, Charles J. Smith) ; also in the 

 Yellowstone region, the Upper Missouri, the Upper Bio Grande, Colo- 

 rado, and the lakes of the Great Basin of Utah, being very abundant 

 in Utah Lake. Xot common south of Mount Shasta in California. 

 This species is apparently the parent stock, from which our other black- 

 spotted trout have scarcely yet become differentiated. Considerable 

 local variations occur, especially in size, coloration, and size of scales. 

 The red blotches on the lower jaw between the dentary bones and the 

 membrane joining them is very constant and characteristic. 



(Salmo purpuratua Pallas, Zool. Ross. Asiat., iii, 374, 1811-31: Salmo clarki Rich. 

 Fauna Bor.-Auier. iii, 224, 1833 : Fario stcllatus Girard, Proc. Acad. Nat. Sci. Pbila. 

 1856, 219: Salmo brevicauda Snckley, Aim. Lye. Nat. Hist. N. Y. vii, 308, 18G1: Salmo 

 gteUatns, gibbsi, arid brevicauda Giinther, vi, 117-129: Salmo clarki Jordan, Proc. U. S. 

 Nat. Mus. i, 77 : Salmo tsuppitch Jordan, Proc. U. S. Nat. Mns. i, 72; Fario aurora Girard, 

 Proc. Acad. Nat. Sci. Phila. viii, 218, 1836: Salar lewisi Grd. Proc. Acad. Nat. Sci. 

 Phila. 1853, 219 : Salar virginalis Girard, 1. c. 220 : Salmo carinatus Cope, Haydeu's Geol. 

 Surv. Mont. 1871, 471-472: Salmo utah Snckley, Moriogr. Salmo, 138: Salmo aurora, 

 lewisi, and virginalis Giinther, vi, 119-123.) 



Var. boBivica'i Bendire. Walia Lake Trout. 



Similar to S. purpiiratus, but with dark spots only on the dorsal, cau- 

 dal, and adipose fin, and on the tail behind front of anal, where the 

 spots are very profuse, smaller than pupil. Anterior regions dusky 

 bluish, not silvery; red blotch on inner edges of deutary bones below 

 very conspicuous. Head shorter and deeper than in purpuratus, the 

 snout shorter and blunter, not longer than eye, which is 4 in head. 

 Opercle and preopercle less convex than in purpuratus. Maxillary 24- 

 in head. Caudal moderately forked. Head 4; depth 4. D. 10; A. 11; 

 B. 12; Lat. 1. 175. Size small. A singularly colored local variety, found 

 in Waha Lake, Washington Territory, a mountain lake without outlet. 



(Salmo lousieri Beudire, MSS.) 



