18 SALMON AND TROUT IN ALASKA. 



The ventral surface is immaculate, including all the lower fins. The fine punctula- 

 tions with which the upper parts are shaded extend from just behind the gill-openings 

 to slightly below the lateral line and posteriorly approach more and more the ventral 

 surface until, at the caudal peduncle, they reach the lower fin membrane. The indi- 

 vidual punctulations are larger and more separated on the lower side; the close setting 

 above gives the back a marked dusky color. The membranes of the rayed dorsal and 

 the caudal are similarly dusky. A single row of small blotches sometimes merging 

 together occupies the median dorsal line from top of head to base of caudal. Along 

 the lateral line or a little below it anteriorly the parr marks appear, from seven to ten 

 small, rounded, or elliptical blotches about half the diameter of the eye and more or 

 less evenly distributed between the gill-openings and base of caudal ; the depth of color 

 and the approach to circularity of outline increase toward the caudal region; a dark 

 spot on the opercle and one at the base of caudal complete this row. A second row of 

 similar but smaller blotches sometimes appears between the lateral row and the median 

 dorsal line. In transparent specimens the black of the inner ventral linings may show 

 through slightly. Tip of chin dusky. 



The small fingerlings (pi. i, fig. 2), 35 to 50 mm. in length, show some change in 



shape. The caudal peduncle becomes slim in propor- 

 /_ _ ,X__^ . ^^'^ *^^^ ^° *^^ length and the general outline is more 



^s^^V^^ Zl^^^r-^ C tapering; the greatest depth, at a point about midway 



\S\'\y ^^"^ between base of pectorals and front of dorsal, is about 

 ^=v 5 in body; both ventral and dorsal outlines are more 



/ y -^""^ nearly straight to base of caudal than in small fry. In 



y^ V} ZZ~^ \ ^*'*§^'' ^nd well-fed examples the ventral outline is 



^^i^^^l:i_— "YT^^^T*/' ^^"O slightly more arched. In poorly nourished and 



unthrifty examples the greatest depth is through base 

 Sockeyo fingerlings. Upper figure a , ^ i ^i, j i j i i i j i *i,- 



poorly nourished example, lower of pectorals, the caudal peduncle looks deep and thin 



well nourished. ^^ comparison, and the depth in front of dorsal is 



less than one-fifth the body length. (See text figures.) 



In markings the general duskiness encroaches on the ventral region, only the belly, 

 breast, and lower head parts (except the chin) remaining immaculate. The median 

 dorsal marking may be a row of blotches', or these may merge into a nearly solid stripe, 

 which in individuals of 50 mm. up usually fades into the general duskiness. In most 

 of the smaller individuals the parr marks are rounded blotches little larger than the 

 pupil, varying in number from 8 to 12 and more or less evenly distributed along the 

 lateral line. The second row above may or may not be present. 



Specimens from Karluk between 40 and 50 mm. long show considerable variation from 

 the markings just described. The parr marks are elliptical, about twice as deep as 

 wide, except over anal and on peduncle. These long bars are mainly below the lateral 

 line. They much resemble the markings of the dog salmon. These specimens also 

 vary from the more southerly examples in the smallness of the eye and in the fewer 

 and shorter gillrakers. Their identification is not absolute. 



At about 80 mm. length (pi. ii, fig. 1) the fingerling asslimes the graceful outlines 

 of the adult, depth 4.5-5 in body, average 4.6; head 3.66-4.12, average about 4; eye 

 nearly 3 in head, pectorals 1.5-2, average 1.66; dorsal 1.66-2.3, average 1.8; anal 

 about 2.5; ventrals about 2; gillrakers very variable, 12-20 to 13-22; longest | to once 

 diameter of eye, spanning 3 to 6 interspaces. In fresh water the general color is silvery 

 over dark. Punctulations cover the entire body, except a narrow area between chin 

 and ventrals. The parr marks are more or less elliptical, with a depth about equal 

 to diameter of eye and almost obliterated by the silvery. Occasional fresh-water 

 specimens wholly silvery, sea-run individuals probably always so. 



A yearling (pi. v), from Karluk Beach, 165 mm. in length, had depth 5; head little 

 more than depth, 4.5; eye about 3.5 in head; pectoral 1.5; dorsal 2.2; anal 2.66; ven- 

 tral 2; gillrakers as in adult — that is, having about the same proportion to diameter 



