152 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



It is to be noted, however, that comparatively small 

 plaice have been found to be sexually mature. Some 

 females of 29'5 to 30*5 cms. (12 inches) were spawning 

 fish, and a fairly large proportion of male fish from 25 to 

 30 cms. (10-12 inches) long were mature and had fully 

 developed testes. This was the most novel part of this 

 section of the investigation. We had not previously 

 suspected that sexually mature plaice were so small, as 

 the above figures indicate. The ages of these male plaice 

 were over three and less than four years. The mature 

 females were very seldom less than four years old. It 

 has been suggested by Kyle that on intensely fished 

 grounds the average size of plaice, when they first become 

 mature, is becoming less, and this hypothesis is very 

 probable. But another reason may well be that we simply 

 have not looked for these plaice in former years. 



