106 



Table XV. Age Groups : Data for Group I, 1908-1916. 



to any particular group. Really the odds will be a little 

 different when we apply certain necessary corrections, but we 

 shall only do that when required by the administrators. This, 

 then, indicates the way in which this (and the other) tables 

 ought to be used practically. 



Fig. 7 is a graph of the results of Table 14. It shows the 

 average lengths of plaice of Age-groups to IV, and also the 

 " dispersions," so that some idea of the significance of the 

 overlapping of the various group-lengths may be obtained. 

 The graph is not a straight line, but a logarithmic curve of a 

 kind, and to see how this is we must consider the sizes of 



