NORTH SEA INVESTIGATIONS. 379 



contain a few ripe ova at the end of August, The condition of 

 other large females at about the same time and in the early part 

 of September seems to indicate that some spawning will take place 

 in the autumn, on the Iceland grounds, at any rate. Very likely, 

 as in the case of the haddock, the North Sea fish spawn earlier, 

 but of this I have no evidence. 



The fish enumerated below were examined at various dates 

 between February and September (inclusive), and do not take into 

 account a number of large fish which I have looked into from time 

 to time, in the hopes of finding ripe ova. 



Owing to the large size and high price of halibut, their purchase 

 in any considerable number was out of the question. I have, 

 therefore, had to depend, for the most part, on eye observations made 

 in the market, checked so far as possible by the careful examination 

 of a limited number in the Laboratory. In the case of females, the 

 method of observation is indicated in the accompanying figures. 



Total number of fish examined, 150 ; males, 64 ; females, 86. 



Males. — Immature. — 1 at 15 inches, 2 at 16, 1 at 19, 1 at 20, 



2 at 21, 2 at 22, 1 at 28, and 1 at 29. 



Approaching ripeness. — 1 at 24, 1 at 25, 1 at 27, 1 at 28, 6 at 30, 

 4 at 31, 4 at 32, 2 at 33, 4 at 34, 3 at 35, 1 at 36, 3 at 37, 1 at 38, 

 and 9 from 34 to 37. 



Ripe.—l at 31, 1 at 37, 1 at 38, 1 at 41, and 2 over 50. 



Spent.— 1 at 30, 1 at 31, 1 at 33, 2 at 34, and 1 at 35. 



It appears, therefore, that the male may be mature at about 

 30 inches, and is probably never mature at less that 25 inches. 



Females. — Immature. — 2 at 14 inches, 1 at 16, 2 at 24, 2 at 30, 

 1 at 31, 2 at 32, 1 at 33, and 1 at 35. Examined in the Laboratory. 



Immature, or very little advanced towards maturity. — 4 at 28, 



I at 29, 3 at 30, 2 at 32, 5 at 33, 4 at 34, 4 at 35, 3 at 36, 2 at 37, 



3 at 38, 1 at 39, 1 at 40, 2 at 41, 2 at 42, 1 at 44, 1 at 47, 1 at 49, 



II from 37 to 47. Examined in the market. 



Approaching ripeness, ovaries distinctly enlarged.. — 1 at 43, 

 1 at 45, 1 at 49, 1 at 50, 1 at 56, 1 at 59, and 15 over 60. Exa- 

 mined in the market. 



Ripe. — 1 at 73 inches. 



The inference is that, if the observations made in the market are 

 approximately correct, the female does not spawn until she is about 



4 feet long ; but I would prefer to await the results of continued 

 work in the later months of the year, and to make use, pro tern., 

 of a limit of only 36 inches. 



