84 UNIVERSITY OF COLORADO STUDIES 



in the loss of the orange tip to the adipose fin. It has been noted' that the Loch 

 Leven Trout when introduced into the streams of Yosemite Park reverted to the 

 typical Brown Trout with bright-red spots and orange-tipped adipose. It is 

 entirely possible that such a change may have taken place in the Loch Leven 

 Trout planted in this state so that any caught will probably be the true Brown 

 Trout as regards, markings. No specimens of this trout taken in Colorado have 

 been examined by the writer. 



Genus SALVELINUS Richardson 

 The Charrs 



Salvelinus Richardson, Fauna Boreal. Amer-, Vol. Ill, p. 169, 1836. 



Species of this genus in general appearance are much like those of the genus 

 Salmo, from which they may be separated by the boat-shaped vomer, the smaller 

 scales, of which there are 200 or more cross-rows, by the round, bright-red or 

 crimson spots on the sides of the body, and the white or orange edgings to the 

 anterior margins of the pectoral, ventral and anal fins. Pyloric coeca 35 to 50. 

 Species of this genus are known from both the Old and the New World, inhabit- 

 ing cold and rapid waters of small streams. Salvelinus is represented in Colorado 

 by the Eastern Brook Trout, an introduced species. 



Salvelinus fontinalis (Mitchill) 

 Eastern Brook Trout, Speckled Trout (Figs. 39, 40, 41, 42 and 43) 



Salmo fontinalis Mitchill, Trans. Lilt. Phil. Sac. N.Y., Vol. I, p. 435, 1815 (near New York 

 City). 



Salvelinus fontinalis (Mitchill) — Jordan, Bull. U.S. Fish Com., Vol. IX, p. 16, 1889 (reported 

 as introduced into Twin Lakes); Juday, Bull. U.S. Fish Com., Vol. XXVI, p. 162, 1906 (Twin 

 Lakes); Cocbcerell, Univ. Colo. Studies, Vol. V, p. 175, 1908 (Allen's Park, Boulder County). 



Head 4 to 4. 5, depth about 4. 4 in the length; dorsal rays 10 or 11, anal rays 9. 



General color dusky to dark green, sides lighter, shading to pale yellow or 

 reddish below; top of the head quite dark; body above the lateral line dark, 

 mottled and marbled with dark olive-green but without spots except near the 

 lateral line; two or more irregular rows of black and crimson spots, the latter being 

 smaller than the pupil of the eye, in the lateral line region; ventral parts lighter, 

 varying from pale yellow, to bright orange-red in breeding males; pectoral, ventral 

 and anal fins with a rather broad, yellowish or orange area along their anterior 

 margins, this area edged posteriorly with black or dusky; lower margin of the 

 caudal fin marked in much the same manner; dorsal fin dusky, quite dark at the 

 base, crossed by several irregular and broken bars of black or dusky; parr marks 

 in the young quite distinct, often persisting as faint dusky, vertical bands on fair- 

 sized individuals; size small to moderately large, average specimens usually 12 

 inches or less; in Maine specimens have been taken weighing 6 pounds or more. 



' Jordan, Science, N.S., Vol. XXII, p. 714, 1905. 



