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BULLETIN OF THE BUREAU OF FISHERIES 
and size distributions from Eshamy and McClure Bays differ considerably from those 
of the area under consideration (Rounsefell, 1930, pp. 299-301). However, the age 
distributions from four localities for 1929, given in Table 10, show a close agreement, 
justifying our disregard of possible racial differences in studying dominant year classes 
in these areas. 
Table 10. — Age distributions from four different localities in Prince William Sound for 1929 
The body lengths used in this analysis of size fluctuations were measured to the 
nearest millimeter. (Rounsefell, 1930, p. 239.) The lengths were grouped in 5-milli- 
meter categories, and then smoothed twice by threes in order to remove minor modes 
due to chance sampling. These length distributions (fig. 8) show the progression 
from year to year of four distinct modes through the catch. The two modes (. A and 
B), present in 1924, are plainly discernible in 1925, but in 1926 and 1927 they have 
become fused into a common mode, due, probably, to a decreasing difference in growth 
rate; the small mode ( D ) which first appears in 1926 may be traced through 1927 and 
1928. The most prominent mode (F) appears in 1927 and advances through 1928, 
1929, and 1930. During these two latter years this mode dominates the field, there 
being no minor modes. The troughs at C and E are best explained in the following 
paragraphs. 
Table 11. — Percentage length frequencies for June and July from the vicinity of Lalouche smoothed 
