650 REPORT OF THE COUNCIL. 



Section II.— HYDROGRAPHIC AND PLANKTON WORK 

 IN THE ENGLISH CHANNEL. 



The English portion of the international scheme of hydrographic 

 and plankton observations, the execution of which has been assigned 

 to the Marine Biological Association, is to be carried out in the western 

 half of the English Channel. 



These investigations have for their object the study of the seasonal 

 changes which take place in the physical and biological conditions pre- 

 vailing over the entire region covered by the international programme, 

 though more particularly directed to a study of the waters entering the 

 North Sea from different directions. They are designed to determine 

 (1) the origin, history, and physical and biological characters of the 

 water found in each locality at different seasons of the year and at 

 corresponding seasons in different years, changes in which must neces- 

 sarily have a profound influence upon the distribution and abundance 

 of the fish-life in the sea, and (2) the variations which take place in 

 the floating and swimming organisms (plankton) which constitute the 

 fundamental food-supply of the sea. 



A. METHOD OF INVESTIGATION. 



The investigation is being carried out (1) by means of a series of 

 quarterly cruises made simultaneously over the whole area by the 

 vessels of the participating countries, as a result of which a thorough 

 knowledge, based upon the most accurate available methods, is obtained 

 of the conditions prevailing at all depths at certain fixed stations, 

 together with a less detailed knowledge at intermediate points ; and (2) 

 by observations, more especially of the surface conditions, at as many 

 points as possible during the time intervening between the seasonal 

 cruises. 



The particular portion of the work which falls to the lot of the 

 Marine Biological Association may now be described in more detail. 



I. Seasonal Cruises. 



The seasonal cruises are carried out as nearly as circumstances will 

 allow during the first fortnights of February, May, August, and Novem- 

 ber, with the view of studying in detail the mid- winter, mid-spring, mid- 

 summer, and mid-autumn conditions. 



The following twenty stations in the western half of the English 

 Channel are to be worked on each cruise : — 



List of Stations. 



I. 10 miles S.W. | S. southerly of the Eddystone. 

 II. 47 „ „ „ „ „ „ (mid-channel). 



