14 SALMON AND TEOUT IN ALASKA. 



In life, back green to bronzy^ changing to indigo blue upon death.; the sides sil- 

 very with brassy luster and green tints; ventral surface silvery white, usually with- 

 out marks of any kind, but rarely with a few faint short parr marks above the lateral 

 line; a narrow median dark line on back; membranes of caudal greenish, with black 

 punctulations; dorsal similar with a narrow darker front margin; pectorals and lower 

 fins colorless; iris greenish silver. 



In preserved specimens, particularly formalin specimens, a magnifier shows minute 

 punctulations over almost the entire side, the back, and the dorsal and caudal mem- 

 branes, and sometimes on the maxillary, chin, and throat. 



The humpback fingerling (pi. ii, fig. 2) is little changed from the fry described, 

 except in size. It is the most slender species of the genus, with head long and pointed. 

 In 20 examples from Karluk Beach 65 to 92 mm. in total length, the average depth 

 was 5.57 in length to base of middle caudal rays, extremes 5.12 to 6; in 6 examples 83 

 to 92 mm. long the depth was 5.54, head 4.4, eye 3.8 in head, pectoral a little less 

 than 2, dorsal 2.26, anal a little more than 3, ventral 2.46. Brancliiostegals 11-12 to 

 12-13; gillrakers 10 to 13 upper limb and 16 to 19 in lower limb, longest from IJ to 

 1^ times diameter of pupil and spanning 4 to 5 interspaces. The length and number 

 of the gillrakers is not infrequently greater than in the sockeye fingerling, but the 

 absence of visible scales in the smaller individuals, and their delicacy and small size 

 in the larger of the humpbacks, as well as the more slender body outline, will distin- 

 guish these fingerlings from the sockeye. In the adult humpback the gillrakers are 

 11-17 to 13-19, the longest If to 2 times diameter of pupil, covering 4 interspaces. 



Colors of the fingerling: The dusky of the dorsal shows as a diffuse blotch on the 

 front and distal portions, the dusky of caudal more intense toward the points of the 

 lobes and at the base, but less marked than in the dog salmon; a little dusky 

 appears in the axil of pectoral. A few small black blotches on the upper side were 

 noted in a few of some fingerlings reared at the Clackamas station. 



At this stage the scales, though very thin and delicate, may be made out with a 

 magnifier or a good eye. The lateral line is a mere furrow and shows no tubing. In 

 the dog salmon of the same or much less size the scales are evident and tubes of the 

 lateral line distinct. 



In the Karluk specimens examined the ovaries are ribbon-like, whereas in other 

 species the ovaries are more cylindrical and usually somewhat swelled at the ante- 

 rior end. 



The Dog Salmon, Oncorhynchus keta (Walbaum). 



The dog-salmon fry (pi. i, fig. 5) attains a length of about 40 mm. by the time the 

 ventral walls are fully united, perhaps a greater length than the fry of any other salmon 

 of the genus. It resembles the humpback in general shape. Greatest depth just 

 behind pectorals, 5.5 to 6 in body; head 4; eye about 2.66 in head; pectoral 1.75 to 2; 

 dorsal about 2; anal about 2.5; ventral equal to anal; gillrakers little more than 

 tubercles, about 5-11 to 12 may be made out, longest about one-fourth diameter of 

 pupil, equal to about one interspace. 



In life, ground color bright grass green, becoming slightly darker on back. and paling 

 on lower side to an overcast on the silver; occasionally a brassy luster on back; lower 

 parts silvery with the palest green iridescence; back with very fine black punctula- 

 tions, fusing into numerous small black spots about the size of pupil from nape to base 

 of caudal; a median dark line on back in front of dorsal, not marked back of dorsal. 

 The punctulations cover sides to axil of pectoral in front, to about halfway between 

 lateral line and ventrals, and sun-ound caudal peduncle, becoming coarse and scat- 

 tered below. The parr marks, from 6 to 12 in number, lie mainly above lateral line. 



