records 85 species from the Malay Archipelago in his report published in 1901. Dr. R. N. 

 Wolfenden reports on iiS species frorh the plankton collected by J. Stanli s Gardiner around 

 the Maldive and Laccadive Islands. Professor W. A. Herdman's collections from the Gulf of 

 Manaar f902 [903 produced [95 species. 



The following table gives the families and divisions represented in the present report, 

 with the number of species belonging to each, and shews the difference between the results 

 obtained from the investigations of the 'Siboga' when compared with the parts of the Indian 

 Ocean referred to. 



'Siboga' 



195 



118 



85 



None of the above lists are strictly comparable with each other, as the methods employed 

 in collecting- the material were not identical in every case. For instance : — No vertical hauls 

 with the Hensen net were taken in the Gulf of Manaar. During the 'Siboga' expedition fifteen 

 such hauls were taken from depths between 10 metres and 2000 metres. On the other hand 

 we examined se ven collections of washings from invertebrata dredged around Ceylon, compared 

 with the three in the present report. Wolfenden does not give any information about the 

 methods employed by J. Stanley Gardiner in taking the collection of Copepoda from around 

 the Maldive and Laccadive Islands, nor are the exact positions given for the occurrence of 

 the species although the two groups of Islands are roughly 200 miles apart. The species 

 recorded by Wolfenden, are such as would lead one to suspect that the Copepoda were 

 obtained from at or near the surface, and at 110 great distance from the Islands. The collection 

 reported on by the late Professor Cleve appears to have been purely a surface series. 



Unless one can deal with Copepoda that have been collected by similar methods in 

 different areas for some considerable period, it would be pure speculation to attempt to explain 

 the differences that are apparent in the four series given above, and any conclusions put forward 

 must necessarily be fallacious to a very considerable extent. It is hopeless at present, for instance, 

 to compare the Copepod fauna of the sea along the coast of Western Europe, with that of 

 almost any other part of the world. The Copepoda of the seas round Northern and Western 

 Europe have been investigated by different observers for nearly a century, and yet a dozen 

 years ago not even the most optimistic student had any idea that the very deep region to the 

 West of Ireland and North of Scotland, was populated with so many interesting species as 



3 



