227 
with large trawls, heavy catches and long drags, most fish 
are dead when the net is hauled. The success of such a 
measure would therefore depend to some extent on the 
possibility of devising a mesh of such form and dimen- 
sions as would capture only moderately large Plaice with- 
out prejudice to the capture of other (round) fish trawled 
for. 
As far as inshore fishing is concerned the “ vitality ” 
experiments made by Mr. Dawsont for the Lancashire Sea 
Fisheries Committee have shewn that with moderately 
short drags (one or two hours) both with fish and shrimp 
trawls a great proportion of Plaice (81 per cent.) recover 
when taken from the contents of the net and placed in 
running sea water. The relative catching powers of nets 
with different sizes of meshes have also been ingeniously 
illustrated by the same writer. An ordinary fish trawl of 
20 feet beam and with a square mesh of 7in. periphery 
was used. Round the catching portion of this net a 
similar net but with a mesh of 44in. periphery was laced. 
The combined net was dragged in the ordinary manner. 
Fishes which passed through the inner wide meshed net 
were retained in the outer one. In one such trial the 
inner 7in. net captured 41 Plaice of about 9 inches in 
length, while the outer 4}in. net caught 349 Plaice of 
about 54 inches in length which had passed through the 
inner net. In another trial of this combination net the 
Tin. net caught 142 Plaice 74-94 inches long, and the 
outer 44in. net 390 fishes of 44 inches long. Correspond- 
ing results were obtained with the other fishes captured.} 
Petersen’s “ growth-theory,” it will be seen, proposes 
to remedy the exhaustion of the Plaice fishery by raising 
+ See Lancashire Sea Fish. Laby. Rep. for 1893, p. 23. 
t See Holt—Journ. Mar. Biol. Ass., vol. iii., pp. 437-441, 1895, for a 
discussion of the probable results of regulation of the trawl mesh. 
