80 NORTH SEA INVESTIGATIONS. 
though in this respect the species before us is less particular than 
some others, are known not to take a bait very readily. Moreover 
a good part of them are inshore fish, and on this coast the cod 
appears to spawn chiefly off shore. Hence it may be that the 
percentage of immature indicated by the table is somewhat too 
high to be applicable to the whole species. My inquiries are not 
yet complete, and I have therefore chosen a provisional limit which 
is very unlikely to have to be lowered. 
It appears from Fulton’s observations (Rep. 8. F. B., 1892, Tab. v, 
p. 239a) that on the east coast of Scotland the female may be 
nearly mature at 21 inches, and this, no doubt, occurs in exceptional 
cases in other parts of the North Sea. My own results show very 
little difference between males and females in the size at which 
maturity is reached, which is the less remarkable since the two sexes 
do not greatly differ in size ; indeed, according to Fulton (op. cit., 
1890, p. 247), the male is the larger fish of the two. The same 
authority, however, found the females to be the most numerous, and 
such is my own experience as regards specimens of all sizes. It is, 
therefore, rather singular that my table, which includes all the fish 
of the given sizes which I could procure here, shows an almost exact 
equality of number. The manner in which they were caught, 
which has a tendency, as I have mentioned, to be less efficacious in 
the case of gravid females, may partly explain the phenomenon so 
far as it is apparent in the case of the larger sizes in the table. 
Haddock (Gadus xglefinus). 
Provisional size-limit, 13 inches. 
It appears from the limited number which I have as yet examined 
that the average size at which the female begins to spawn is about 
13 or 14 inches. The largest immature and the smallest nearly 
mature examples of this sex measured 16 and 11 inches respectively, 
and the smallest fully mature specimen 15 inches. ‘The male seems 
to mature at a somewhat smaller size, viz. about 11 inches; all 
males of less than 10 inches were immature, and in fish of less than 
9 inches it was very difficult to find the testes at all. All of more 
than 12 inches were mature or nearly so. Fulton’s table (loc. cit.) 
appears to indicate a very similar experience as to facts, and it is 
evident that the pre-eminence in size which this authority ascribes 
to the male is no bar to the latter attaining maturity at a smaller 
size than the female. If we assume that rate of growth is propor- 
tional to size, it would seem to follow that the duration of repro- 
ductive life must in this case be greatest in the male. ‘That the 
same difference in attaining maturity is less apparent in the cod is 
