215 
thing with much older Plaice), or they migrate to the 
deeper portions of the nursery ground such as the 
channels. The latter seems to be the case with the Mersey 
nursery. Great quantities of young Plaice are to be found 
there on the sandbanks, where the water is shallowest, 
during July, August and September, maximum quantities 
being taken in the latter month. During the winter 
months, however, comparatively few are found there, but 
they are abundant in the channels where the water is 
deeper. This local migration then goes on independently 
of the larger movement. The Plaice move from the 
shallow water to the deeper as the colder months approach 
and from the deeper water in the channels to the shallow 
banks as the temperature rises. 
The young Plaice on these nursery grounds form part 
of an exceedingly abundant vertebrate and invertebrate 
fauna. They are associated with other Pleuronectid and 
Gadoid fishes—the dab, flounder, sole and solenette (Solea 
lutea), with occasionally young brill and turbot and the 
whiting, haddock and cod. Young sprats (Cluped 
sprattus), sand-eels (Ammodytes), Cottus,  sting-fish 
(T'rachinus) and Centronotus are also found; all these with 
the exceptions of the sting-fish, sprat and solenette are 
young and immature fish. Of the Gadoid fish the whiting 
are very abundant. These are young fish, in their first 
year probably, and generally not exceeding five inches in 
length. The invertebrates are usually crabs (Portunus) 
and star-fish (Astervas), and great numbers of shrimps 
(Crangon). The crabs alone often form nearly half the 
total bulk of the catch. 
These young fish are continually being captured in 
the shrimp trawl, which having a square mesh of 3 inch 
side, retains them. We may quote one single catch to 
give an idea of the bottom fauna of the Mersey nursery 
