HOEK— INTRODUCTORY 



II — 



they will certainly contribute greatly to the better comprehension of the changes in 

 the plankton according to the seasons of the year and' conditions of the currents. 



Here follows a list of the specialists who have been engaged in the determina- 

 tion of the plankton-forms in the different countries: 



Belgium: Professor G. Gilson and Prof. Meunier for the vegetable plankton, aided 

 by Dr. H. van Heurck and Dr. H. H. Gran, and by Prof. G. O. Sars for the 

 Crustacea. 

 Denmark: Museumsinspektor C. H. Ostenfeld for the phytoplankton and Tintin- 



noidea, Dr. C. Wesknberg-Lund for the Zooplankton; Mag. Sc. Ove Paulsen for 



the phytoplankton and Tintinnoidea (Atlant. Ocean). 

 England: Dr. L. H. Gough, aided by Dr. A. M. Norman, R. H. Worth, E. T. Browne, 



W.Wallace, Dr. E. J. Allen, Dr. Th. Scott and W. J. Beaumont. 

 Fi7iland: Dr. K. M. I^evander. 

 Germany: Dr. C. Apstein; his assistants in the work were Cand. Phil. Conrad, Dr. 



Zander and Dr. Rauschenplat. 

 Holland: Doctorandus P. J. van Breemen, aided by Dr. J. Bo eke. 

 Norway: Dr. H. H. Graîs'; assistant, Cand. Hjalmar Broch. 



Rttssia (Murman coast): Prof. P. T. Cleve (phytoplankton). Dr. A. Linko (Zooplankton). 

 Scotland: R. M. Clark (plankton with exception of the Crustacea), Dr. Th. Scott 



(Crustacea). 

 Sweden: Professor P. T. Cleve. 



The following list gives information concerning the number of the expeditions 

 and stations at which plankton was collected during the seasonal cruises, and 

 concerning the divisions of the sea investigated. 



Number of the plankton-stations, hauls at each station etc. 



Countries 



Region of the sea 



Number 



of 

 stations 



Number of 



plankton 



tables 



delivered 



When fished 



Belgium / 



DeniDark ' 



England 



Finland ] 



Germany ^ 



Holland 



Norway 



Russia 



Scotland 



Sweden } 



Eastern entrance of theChannel, southern 



part of the North Sea 



North Atlantic Ocean 



Danish Waters 



English Channel 



Gulf of Bothnia 



Gulf of Finland 



Baltic 



North Sea 



Baltic 



North Sea, southern part 



Norwegian Sea 



Arctic Ocean 



North Sea, northern part 



Skager Rak 



Baltic 



'I'he Sound 



>9 

 i6 



14 



24. 



12 



9 

 44 

 21 

 24 

 16 



9 

 I 



since August 1903 

 only in May and August 

 since November 1902 

 » February 1903 



l\Iay 1903 



» » 

 November 1902 

 February 1903 

 August 1903 

 May 1903 

 August 1902 



