160 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



months there were a few hundred in a haul. Rockling and 

 other fish eggs were present from January to October and began 

 to appear again at the end of December. On the whole these 

 distributions corroborate more or less the experience of previous 

 years. 



When the special hauls taken during the Easter and 

 summer vacations in the open sea outside are compared with 

 those taken across the bay at the corresponding seasons, it is 

 found that in all groups the numbers per haul are usually 

 higher out at sea. The Copepods were in force outside rather 

 earlier than in the bay-, the maximum for the adult Copepoda 

 being in August at sea and in September inside the bay. In 

 other groups there is no great difference in time. 



Finally, it may be remarked in connection with the point 

 discussed in our report last year as to the degree of correspon- 

 dence in time between the hatching of larval fish such as plaice 

 and the appearance in the sea of phytoplankton in abundance, 

 that 1920 may have been a year when microscopic food for the 

 first hatched young fish was scanty in amount. The fish- 

 hatching at Port Erin was unusually early (February) and the 

 Diatoms at least were not present in great abundance until 

 later than usual. It must be remembered, however, that in 

 addition to Biddulphia and Coscinodiscus, which reach their 

 maxima in March, various larval forms of Invertebrata such 

 as Polychaets and Mollusca are present in considerable abun- 

 dance in the early spring months and may serve in part, along 

 with the phytoplankton, as food for the young fishes. 



