174 
PACIFIC SCIENCE, VoL VII, April, 1953 
our sample is reasonably representative of the 
commercial catch; also, that its use avoids an 
error likely to be introduced when only the 
individual relationship, body length-scale 
length, is used, i.e., the error caused by the 
use of scales of different parts of the body. 
SUMMARY AND CONCLUSIONS 
To determine what method will most ac- 
curately serve to back-calculate lengths of 
pilchard at earlier ages, covariance analysis of 
observed scale and body-length regressions 
is useful. Emphasis is given to the most ap- 
propriate sampling criteria to be used in order 
to get the regression values, as well as to the 
actual method of sampling. 
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7-174, 10 figs., 1 pi. 
1913. Further studies concerning the 
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Cons. Perm. Internat. h'Explor. Mer, Puhl. 
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