224 



BULLETIN OF THE BUREAU OF FISHERIES 



Only one individual with this mark was recovered. This fish was found by a 

 Chinese butcher at one of the canneries in Astoria, who preserved the scars but no 

 other data. The mark is perfectly clear, although it is worthy of note that the 

 posterior half of the dorsal fin had not grown normally. The rays were short, and 

 their tips bent backward as though the resistance of the water had modified the 

 growth as the growth of trees is modified by the prevailing winds. The exact date 

 of capture is not known, but it was some time between May 25 and June 21, 1920. 



The scales of the adult fish (fig. 11) show clearly the four complete years of 

 growth and a narrow marginal band of M'ide "summer" rings, which represent the 

 beginning of the fifth year's growth. vScales from the skin attached to the scars were 

 the only ones available for study, as a sample of scales taken from the central por- 

 tion of the body was not preserved. While the details of the life liistory may be as 

 readily obtained from perfect scales taken from unusual regions of, the body as from 

 the more typical ones taken from the central portion, they are not as satisfactory 

 for comparative studies. In this case, for instance, it is not as easy to compare the 

 nuclear portion of the adult scale with the scales taken from the young fish preserved 

 at the time of marking. Taking this into consideration, the nuclear portion of the 

 adult scale (fig. 12) does, however, correspond fairly well with the typical scales of 

 the young fish (figs. 9 and lOV 



EXPERIMENT NO. 3.— LITTLE WHITE SALMON RIVER HATCHERY, JULY AND AUGUST, 



1916 



Eggs from: Little White Salmon River, 1915. 



Reared and marked at: Little Wliite Salmon River hatcliery. 



Mark xised: Removal of left ventral fin and the po.sterior half of dorsal fin. 



Number marked: .50,000. 



liberated: In Little White Salmon River during .July and .\ugust, 1916. 



Age: .Approximately 10 months. 



The average length of 50 unselected specimens preserved on July 2S, 1916, is 



54.4 millimeters (2.1 inches). The scales have an average of 4.8 rings and an aver- 



20 2 . . ... 



age anterior radius of ^^ millimeters. Table 3 gives in detail the data relative to 



these fish. Figure 13 shows a typical scale from an individual 60 millimeters in 

 length. 



Table 3. — Chinook-salmon fingerlings marked at Ldttle White Salmon River hatchery July 28, 1916 



