KOllTH SEA INVESTIGATIONS. 21 



to suppose that they ever occur in a specimen which has not spawned. 

 In specimens in which the ovary, measured as I have described, is 

 equal to, or greater than a half of the length of the ventral fin, there 

 is no doubt that the fish is spent. So far, my conclusions agree entirely 

 with Mr. Holt. But that observer has rejected the possibility that the 

 spent ovary might go on diminishing until it was as small as in an 

 immature fish, and he does not mention the granular masses at all. 

 My contention is that not only are the granular masses evidence of 

 previous spawning, but that they are rapidly absorbed, so that in a fish 

 over 9 in. long, there may be, some time after it has spawned, no 

 indication left to distin!]juish it from an immature fish, which has never 

 spawned at all. I have reason to believe that this complete reversion 

 of the ovary to the apparently immature condition occurs chiefiy or 

 only in the smaller, i.e., the younger fish, and does not take place 

 to the same degree in fish which have spawned several times. 



On April 15th, I saw thirty boxes of plaice landed from a vessel 

 which had been fishing at Markham's Hole and the Swatchway, 

 grounds to the S.E. of the Dogger Bank, and from twenty to twenty- 

 five fathoms in depth. I bought a sample for examination. There were 

 23 fish in all — 11 females, 12 males. 



Males. Females. 



1 ripe 



2 spent ? 



4 two spent, two ? ... 1 



4 one ripe ... 3 probably spent 



1 spent ... 4 „ ,, 



... ^ » » 



1 spent. 



I could not be quite certain that any of these were really immature. 

 Of the males four were doubtful, two at 10 in., two at 11 in., but I do 

 not believe they were immature. Of the females, the one at 11 in. had 

 no yolk and no granular masses, and may have been immature. Of the 

 three females at 12 in., one showed no masses, the other two showed 

 them very distinctly. Of the four at 13 in., one showed no masses. 

 Of the two at 14 in., both showed the masses. The one at 15 in. 

 showed the masses very distinctly, and was certainly spent. As usual 

 the food was Sukn and other molluscs, worms, and occasionally a small 

 crustacean. 



On May 3rd and 4th, I visited the r.illingsgate Market, in London, 

 where I was introduced to Mr. Johnson, the oiliccr of the Fishmongers' 

 Company, and from him received great courtesy and assistance in my 

 enquiries. He informed me that about a third of the supply of fish 

 received there is lauded by steam cutters, who bring it from ileets of 



