CHINOOK SALMON MARKING, COLUMBIA RIVER 237 



lated in Table 17. The average number of rings was 18.4; the average length of the 



anterior radius was ^ millimeters. These measurements are slightly greater than 



,. ,46.6 .,,. 

 those for the fingerling scales, which averaged 15.3 iings and a radms of Y20 "i""^" 



meters. As a rule the rings were very regularly spaced and unbroken, but there was 

 an occasional incidental check, which probably was formed at the time of planting. 

 In a few cases the typical stream and ocean growths were separated by a few rings 

 of mtermediates. Nuclei of average, large, and small size are illustrated in Figures 

 44, 46, and 47, respectively. 



Table 17.— Chinook salmon marked at Bonneville hatchery during the fall of 1920, when approxi- 

 mately IS months old, and recovered during the season of 19S4 



Scale record, first year 



EXPERIMENT NO. 8.— LITTLE WHITE SALMON RIVER HATCHERY, JULY AND AUGUST, 



1920 



Eggs from: Little White Salmon River, 1919. 



Reared and marked at: Little White Salmon River hatchery. 



Mark used: Removal of adipose fin and left ventral fin. 



Number marked: 24,000. 



Liberated: In Little White Salmon River during July and August, 1920. 



Age: Approximately 10 months. 



A sample of 40 specimens preserved during the course of the marking averages 

 49.6 tnillimeters (2 inches) in length. Their scales average -^^ millimeters in radius 



and have an average of 3.5 rings. (See Table 18.) A typical scale is illustrated in 

 Figure 48. This sample is represented by an unusually large proportion of males, 

 the males exceeding the females nearly 3 to 1. This uneven representation of sexes 



