990 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
very evident that it must differ considerably from. the 
theoretical frequency curve, and I have no doubt that it 
represents the natural distribution of the population 
from which the sample was obtained with greater 
probability. 





Fie. 5. 
(3) The length-weight formula for the Plaice. 
In the tables given in this and the preceding reports 
on plaice measurements the truth of the now well-known 
formula, w=l°, has been assumed. The length (J) of 
the fish is stated in centimetres; the weight (w) in grams; 
and k is a co-efficient which varies from 0°8/100 to 
1:2/100, according to the fishing ground and season of 
the year. The co-efficient & has been calculated from the 
equation 
rape 100 (weight of the catch of plaice in grams) 
(sum of the cubes of the lengths in cents.) 
The cubes of each centimetre group being found and 
multiplied by the number of cases in the group. The 
co-efficient varies from a minimum in December-F ebruary 
