SEA-FISHERIES LABORATORY. 287 



in the net. It will also be seen that slight changes in 

 the position of the ground trawled over influence the 

 nature of the catch very greatly; and that the presence 

 of weed or debris in the net has also a great effect. To 

 obtain a true picture of the kind of fish even on such a 

 small area as the shallow waters of Luce Bay, a number 

 of hauls would have to be taken, employing not only a 

 shrimp net but also such a large-meshed net as was used 

 in the present experiments, and perhaps also, a net of 

 intermediate mesh — say four inches. 



$ ic ii n. 13 i+ 15 16 17 '8 19 2o 

 Fig. 8. — Sizes of the plaice caught in Hauls 2, 7-10. 



Strict account was, however, kept of the plaice over 

 and under 14 inches in length. Those over 14 inches 

 are usually mature, and with the exception of a few males 

 those under that size limit are immature. The results 

 are : — 



Plaice over 14 inches in length ... ... 129 



Plaice under 14 inches in length ... ... 343 



