MARINE FOOD FISHES 117 
ring and subsequent light and dark rings indicate a 
year’s growth. The rings, as a rule, are quite easy to 
distinguish and their number bear a regular relationship 
to the length of the plaice. Thus, in any particular area 
the length of the plaice is an indication of its age which 
can always be confirmed by an examination of the 
otoliths. 
Considerable attention has been paid to the examina- 
tion of otoliths on the Continent and in this country, 
and naturalists are satisfied that otolith examination is 
a reliable source of information. But I will describe 
how every reader of this book can examine plaice for 
himself, and confirm the relationship of the length and 
the age of the fish as indicated by the white rings on the 
otoliths. 
Kivery morning your fishmonger receives with his 
consignment of fish a number of plaice. These are 
neatly laid out on the marble slab, and the housewife 
comes and selects the particular fish she desires, and 
then orders it to be sent home filleted. The fishmonger 
lays the plaice on a board, runs the point of a sharp 
knife down the whole length of the fish on one side of 
the backbone. He then makes a cut through the flesh 
just behind the gill-cover, and with a dexterous sweep 
of the knife the first fillet is cut clean off the bones. In 
a similar manner, a second fillet is taken off the other 
side of the backbone. The plaice is now turned over 
and two more fillets similarly removed. After a plaice 
has been filleted, the bony skeleton is as perfect 
