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k. Eel Investigations. 



Belgium. Des pêches au filet fin de Petersen ont été faites en vue d'évaluer 

 chaque année la quantité de jeunes anguilles arrivant de la mer et pénétrant dans 

 les rivières et les ports. Leurs résultats indiquent que la montée sur notre côte 

 est sujette à variations et n'a pas été abondante cette année. 



Denmark has carried out eel investigation on the Dana Atlantic expedition. 



England. Four samples of elvers collected at fortnightly intervals during 

 the run of elvers at Epney-on-Severn were sent to Dr. Schmidt in July. Two samples 

 of eels from Windermere and Lymington respectively have also been obtained for 

 Dr. Schmidt. 



Records of the ascent of elvers entered on forms issued by the Ministry for 

 distribution to river Conservators and others have been received from the Rivers 

 Dee, Eden and Teify. The records have been sent to Mr. Strubberg at Copenhagen, 

 for Dr. Schmidt. 



1. Limnological Section. 



The programme of work for the various countries concerned are as follows: 



In Holland investigations on the hfe history of Coregonus, salmon and seatrout 

 wdll be undertaken in continuation of the work done in previous years. A 

 report on the plankton of the estuaries of the Rhine will be prepared. 



Ireland will continue work on lake-plankton and the Hfe history of Coregonus. 



In Denmark investigations on the life history of salmon and seatrout will be con- 

 tinued in connection with marking experiments. New investigations on the 

 biology of Coregonus will be instituted. 



In Sweden material for the study of Coregonus will be collected. The work begun 

 on salmon will be continued. 



France will make researches on the life history especially growth and migration 

 of Alosa and Acipenser following the same lines as those agreed upon by the 

 . Limnological Section. 



In Finland investigations on Coregonus and salmon and on the plankton in fresh 

 and brackish water will be continued as indicated in the programme above. 



Denmark. Marking experiments with Sea Trout and age-determinations 

 of Salmon, Trout and Coregonus from various Danish rivulets have been carried out. 



Ireland. The work of the Limnological Laboratory on Lough Derg has been 

 continued, and the distribution of the Phyto- and Zoo-plankton has been regularly 

 observed, and its quantity estimated throughout the year. Investigations have 

 been extended to other lakes in the neighbourhood. Further observations on Core- 

 gonus have been made in the Lough Derg. 



The marking of salmon and the collection of salmon scales from selected rivers 

 has been continued. 



