shewn by the results of the investigations now being carried out on the lines laid down by 

 the Conseil Permanent International pour 1'Exploration de la Mer. 



It is demonstrated in the present report that some of the deep water pelagic Copepoda 

 of the North Atlantic are identical with forms from the deep water of the Malay Archipelago. 

 To suggest that this similarity may be accidental, or the result of ocean currents, would not 

 account for the occurrence of such species in areas so widely apart, unless we know a very 

 great deal regarding the Copepoda inhabiting the vast area of deep water that intervenes. The 

 Hensen net, if it had opened up no other line of observation than that of obtaining a continuous 

 vertical sample of plankton from any depth to the surface, has proved of great service where 

 it has been employed. No plankton observations can now be regarded as satisfactory unless this 

 particular net is extensively employed along with ordinary nets worked at or near the surface. 



An ordinary tow-net is of little use in collecting littoral forms of Copepoda that live at 

 or on the sea bottom and are rarely able to swim any distance. Other methods, such as dredging 

 up samples of invertebrata and mud, and washing out the minute Copepoda, or investigating 

 the shore between tide marks, must be pursued to obtain such types. It would be quite erroneous 

 to suggest that littoral Copepoda are absent from an area that is only investigated by tow-net, 

 should none be found. 



Dr. Wolfenden in his report on the Copepoda collected by J. Stanley Gardiner around 

 the Maldive and Laccadive Islands, attempts to draw some conclusions from the species of 

 Copepoda recorded in his own report when compared with the forms recorded from Ceylon, 

 especially the paucity of littoral forms in the Maldive area, that appear to be based on insuf- 

 ficiënt data. The record of no less than 84 species in the report on the Ceylon Copepoda is 

 chiefly due to a piece of luck, and a suggestion by the writer to save all the debris mixed 

 with the dredged invertebrata that had been brought back. Many of the larger invertebrata 

 had been wrapped in paper previous to being placed in the store tanks, but this became greatly 

 disintegrated in the process of sorting out the material, and added to the labour involved in 

 working through the sand and mud left after the large specimens had been removed. It is 

 certainly more troublesome to work through a bottle of debris, especially when largely mixed 

 with shredded paper, than going over a collection of pelagic forms taken by tow-net. The 

 washings from a sample of pearl oysters from Muttuvaratu Paar presented us with 32 species 

 of Harpacticoida that were not found in any of the tow-net collections, or even in any of the 

 other washings. It must be obvious, that the majority of the littoral Copepoda recorded in the 

 Ceylon report could not have been obtained had we neglected the debris. Of the eight species 

 of Harpacticoida recorded by Wolfenden from the Maldive area, no less than five of them 

 are purely pelagic forms. The other three may have been accidentaly swimming near the 

 surface in very shallow water. There is no evidence in the report that true littoral species of 

 Harpacticoida, Lichomolgidae or Asterocheridae were looked for. The more recent origin of 

 the Maldive group, compared with Ceylon, is not a very satisfactory solution of the apparent 

 paucity of the littoral Copepoda. 



When we find European Harpacticoida like Phyllot/ialestris mysis and Rhynchothalestris 

 rufocincta both present in the Malay Archipelago, one is inclined to regard the apparent absence 



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