98 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



larvae would starve to death. The destruction of larvae through 

 the want of sufficient food is not at all improbable, but this is 

 more likely to be brought about by an early spawning of the 

 adult fishes and a late arrival in the spawning area of the winter 

 and spring diatoms, etc. The investigations carried on by the 

 Lancashire Sea-Fisheries Committee and by the Liverpool 

 Marine Biology Committee, which extend over a period of 

 nearly thirty years, show quite clearly that the arrival and 

 abundance of the spring, summer, autumn and winter plankton 

 varies from year to year. 



Barrow, within recent years, has become a very extensive 

 oil depot, and many millions of gallons arrive in tankers during 

 the year. Many of these tankers burn fuel oil. A considerable 

 export trade to distribute the oil is carried on by smaller 

 vessels. The oil-carrying trade has largely developed since the 

 laboratory was established at Piel in 1897. The whole of the 

 sea-borne traffic passes quite close to the establishment, and 

 any detrimental effect on the life in the channel would not 

 have escaped notice. Large beds of mussels occur in the 

 channel, and there is a general bottom fauna of zoophytes, 

 sponges, echinoderms, worms, Crustacea, mollusca, tunicata and 

 fishes. Fully one-third of the periwinkles landed in the whole 

 of the Lancashire and Western District are sent away from Piel 

 Railway Station. These are collected along the sides of the 

 channel at low- water, and so far as the records show there is no 

 decrease in the output per man. In the period 1906-1914 the 

 mean annual man average was slightly under six tons. In the 

 period 1915-1917 it rose to nearly nine and a half tons. In 

 1920 the mean annual man average was nearly eleven tons. 

 Mussel fishing is prohibited owing to danger of sewage con- 

 tamination, but the beds have not diminished in area or 

 apparent population. Formerly, very large succulent mussels 

 were obtainable inside the dock area. These have practically 

 disappeared since the building and fitting-out of submarines 





