48 
BULLETIN OF THE BUREAU OF FISHERIES 
The lengths 11 given in the following graphs (figs. 15 to 24) were taken from cod 
caught by the Halcyon and the Albatross II, including all those that were tagged 
plus some which were injured and killed. It is not possible to say how nearly these 
hook-caught fish are representative of the population, but there is no apparent 
reason to doubt the adequacy of the samples for the purposes of the present study, 
at least for the sizes large enough to take the hook readily. 
Our length frequencies start from 1923, the first year of the present investigation. 
Prior to then no lengths for cod caught on Nantucket Shoals were available, so that 
we had no means of knowing what a normal year might be or how the sizes would 
fluctuate. That they did fluctuate is shown in Table 28. 
11 All the fish were measured to within the nearest quarter inch and grouped in inch classes, those at the half inch being included 
with the next highest inch; that is, 20>6 to 21J4 inches were classed as 21 inches 
