414 Ey J. ALLEN: 
properly comparable. Thus Wallace’s samples show that Plaice of the 
II Group in August, that is fish two and a half years old, average 6 cm. 
longer in Tor Bay on the South Devon Coast than those in deeper water 
on the Leman Banks in the North Sea, and 11 em. longer than those from 
the shallow water off the coast of Lincolnshire, the Devon fish being thus 
from one to two full years ahead of those from the North Sea. 
This rapid growth of the Devon fish is clearly reflected in the structure 
of the otolith, as will be seen from Fig. 4. The broad white rings are in 
marked contrast to the narrow rings of the North Sea fish (Wallace, 23, 
Rep. III, p. 1424, Figs. 6 and 7). 
The following table (p. 415) summarizes Wallace’s results as to the 
average size of Plaice of the different age-groups in different localities. 
From this table it is possible also to compare the difference in rate of 
growth of males and females. It will be seen that on the whole females 
grow more rapidly than males, and that this difference tends to increase 
as the fish grow older. 
The great differences which may occur in the rate of growth of Plaice 
on different grounds are strikingly shown by the results of the trans- 
plantation experiments carried out by Garstang and Borley in the North 
Sea [Garstang (7), Borley (2), Lee and Atkinson (17)]. Small Plaice 
F a aa 
i | ao | 
a= 
16 = ifs 
ts 
we | + os 
i a i 
$2 —-- it eel 
al | 
nL =5 , 
9| TF +— T 
ll 
< eet —_—— ei | 7 are rea, 
ci} | — 
4; = 
<P ee (iat | 
a eae % 
a a Sales es | 
fe ea i le a 
Moriks ty v vi Vi wy Ix x Nt xl | u WW \Y Vv Vi 
Fic. 6.—Showing growth of fish transplanted to the Dogger Bank in the 
combined experiments of the years 1904-8 compared with that shown 
by the Danish marking experiments in the Horn Reef area in the years 
1908-5. (After Borley.) 
caught on the snallow young-fish nurseries off the Danish and Dutch 
coasts were carried in sea-water tanks to the Dogger Bank, which lies 
in the middle of the North Sea. They were then measured, marked with 
