26 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



"OUR FOOD FROM THE SEA.'' 



It is plain, from questions that have been asked from 

 time to time by readers of these Annual Reports and by 

 visitors to the Biological Station, that some of our 

 supporters, both in Liverpool and the Isle of Man, would 

 be arlad of further information as to the nature of 

 " Plankton," and as to the method and object of that 

 Plankton investigation to which so much attention has 

 been devoted during recent years. I shall therefore quote 

 here, with a few alterations and additions, some 

 paragraphs from an address on " Our Food from the 

 Waters," given before the British Association, at 

 Winnipeg, this autumn — the argument being that the 

 marketable fish which man obtains from the sea and from 

 fresh-waters are ultimately dependent for existence upon 

 the minute plants and animals found in varying quantity 

 in all waters, and known as " Plankton" ; and that in 

 collecting, examining and attempting to estimate the 

 quantities of such organisms, under different conditions, 

 and to account for the marked variations in these 

 quantities, the Biologist is dealing with important 

 economic questions, and at the same time is brought face 

 to face with some of the greatest world problems still 

 unsolved by science. 



It is possible to collect samples of the surface 

 Plankton of the sea in any required quantity per day or 

 hour from an ocean liner going at full speed, and such 

 gatherings have now been made from traverses across 

 several of the great oceans. The method is simple, effec- 

 tive, and inexpensive : and the gatherings, if taken 

 continuously, give a series of samples amounting to a 

 section through the surface layer of the sea, a certain 

 volume of water being pumped in continuously through 



