A CONTRIBUTION TO OUR KNOWLEDGE OP J 
THE GROWTH OF THE PLAICE. 
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By ALEXANDEE MEEK, M.Sc. 
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The chart which accompanies this note has been formed by 
utilising the large number of careful measurements and weights of 
this species made this year in- connection -svith the migration experi- 
ment, together with the similar determinations made for a number 
of years at the trawling excursions, and one or two obtained at 
North Shields. It is meant to indicate the relationship between 
the two ordinary measurements and the w’^eight. 
Each of the squares represents one inch of measurement, and it 
will be seen that when the breadth has been expressed with relation 
to the length, as in this case by the series of small crosses, the 
average result is a straight line, sloping at about 30° with the 
horizontal. The natural tangent of this angle is 0’58, and this 
number may therefore be taken to express the average relation of 
the breadth to the length in the case at all events of the plaice of 
the North East Coast. 
As will be apparent by the numbers at the left hand side of the 
chart, the attempt has been made at the same time to express the 
weight in ounces in relation to the length, and the numbers in this 
case form the series of small dots, together forming the average 
curve shown. I am obliged to my colleague Mr. TI. R. Cullen, M.A., 
for an analysis of this curve of weight. In the first place it is 
clear from the line representing the breadth that that measure- 
ment is practically constant with relation to the length, and 
it may be presumed that the thickness is equally constant. As 
a matter of fact the analysis bears this out. On plotting the 
logarithms of the weight and length, they are found to lie on a 
straight line of slope 3 to 1 ; the curve is therefore of the form 
w = k X P ; or the weight is proportional to the cube of the 
lengtii. This is the relationship for bodies of similar shape, 
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