36 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



fins, and were not returned to the pond, but were put 

 temporarily in hospital tanks in the Aquarium. This 

 leaves four plaice still unaccounted for, but as the water 

 was not entirely drawn off from the deepest corner of the 

 pond these may well have been missed in the probing of 

 the sand at the bottom. 



There were found to be very many of the young plaice 

 which had been hatched in the Institution last Easter, 

 from eggs spawned by the larger fish, and so have been 

 under artificial conditions — made as natural as possible — 

 during the whole of their existence. These young plaice, 

 four to five months old, varied from one to four inches in 

 length (the large variation in size is noteworthy), and 

 seemed active and well nourished. The great majority 

 were left as they were in the damp sand and shallow water. 

 From their habit of burrowing in the bottom as the water 

 retreated it was found to be practically impossible to 

 capture them in large numbers, so as to form even an 

 approximate estimate of their quantity. Some hundreds 

 were picked out for experiments in rearing in the small 

 wooden tanks lately fitted up in the verandah. The 

 young plaice examined were found to be feeding mainly 

 on Copepoda. 



In the pond there were also shown to be some 

 shrimps, a number of young GradidaB (the " Bib " and the 

 " Poor Cod "), and a small shoal of young herring (white- 

 bait size). These must have passed through the pumps 

 from the sea, probably in a larval condition. The bottom 

 of the pond was found to be in a satisfactory condition, 

 and many invertebrates, such as Anemones, Ascidians, 

 Polyzoa, Serpulids, and other smaller things, in addition 

 to Algse, were growing on the stones and side walls - 

 showing that plenty of food was being naturally provided 

 for the young fishes. 



