ÖFVBRSIGT AF K. VETENSK.-AKAD. FÖRHANDLINGAR 1899, NIO 1. 27 



there is still another group which seems to be rather unconcerned 

 by the bottom material. 



It is a well known fact that the greater part of the iu- 

 vertebrate fauna of the Caspian Sea is endemic. Of the forms 

 which are regarded as relicts from a previous connection with 

 the Arctic Sea I obtained only Cardium edule. The crustaceans 

 of a similar origin seem to live exclusively in a greater depth 

 than that prevailing at the places where I had opportunity to 

 dredge. I was especially disappointed in not finding Chiridothea. 

 It is the more peculiar that no other relict forms were obtained 

 as the dredgings were carried on comparatively early in spring 

 before the water had gotten the high summer temperature. It 

 would be of interest to make new investigations concerning these 

 relict forras and the biological conditions during the winter. 



The plankto7i of the Caspian Sea seems to be very poor so 

 early in the spring as in April and May. 



Professor Cleve has been kind enough to look through my 

 samples for the purpose of classifying the diatoms contained in thera. 



At Stat. 2 the plankton contained: 



Coscinodiscus suhtilis Ehb., and the litoral forms: 



Camjpylodiscus echeneis Ehb. 



C. clypeus Ehb. 



C. dcemelianus Grun. 



In the same sample was also found a dinoflagellate of the 

 genus Gonyaulax, but probably representing a new species. 



Stat. 5: the litoral forms: 



Campylodiscus echeneis Ehb. 



C. dcemelianus Grun. 



Stat. 11: 



Coscinodiscus suhtilis Ehb. 



Campylodiscus echeneis Ehb. 



Stat. 12: 



Coscinodiscus suhtilis Ehb. 



At Baku near the small island Nargin the following forms 

 were collected the 21 of May. 



