362 BULLETIN OF THE BUREAU OF FISHERIES 



Table 34. — Rate of growth of all year classes of Saginaw Bay herring, in terms of length and weight, 

 as determined by direct measurement and weighing — Continued 



* Male and female. 



UNCORRECTED AND CORRECTED COMPUTED LENGTHS 



The computed lengths in these tables have not been corrected for disproportionate 

 growth of body and scale. A correction for the error from this source would be valu- 

 able if it could be made for fish of all ages so as to permit comparisons. However, it 

 is impossible to make this correction for the first two years of life because, owing to 

 the lack of fish of these years in my samples, body-scale ratios could not be computed 

 for them. The general conclusions derived from a comparative study of the uncor- 

 rected computed lengths would not be altered by a study of the corrected lengths 

 (see Table 24). The relative rates of growth of the various year classes would be 

 unaffected by the correction. It can not be argued, therefore, that my findings rel- 

 ative to the growth of the herring may be vitiated by the probable inaccuracy of my 

 computed data. 



GROWTH OF AGE GROUPS AND YEAR CLASSES 



Total lengths. — An examination of the vertical columns of figures of Table 34, 

 representing measured lengths, shows that the values for each age group generally 

 are greater in successive years, which indicates that the Saginaw Bay herring of the 

 same age were gradually increasing their rate of growth. This is especially clear for 

 the 3 and 4 year fish. 



