The difference in the plankton composition in oceanic and coastal waters attracted the attention of scientists more than half a century ago. Thus H(?)ckel (1890) devided planktonic organisms into oceanic and neritic species which occur in oceanic and coastal waters respectively. Then Sch(?)tt (1893), Cleve (1896, 1897a, 1897b, 1900) Aurivillius (1898) and Gran (1902) went a little further in using planktonic organisms for the identifi The difference in the plankton composition in oceanic and coastal waters attracted the attention of scientists more than half a century ago. Thus H (?) Ckel (1890) devided planktonic organisms into oceanic and neritic species which occur in oceanic and coastal waters respectively. Then Aurivillius (1898) and Gran (1902) went a little further in using planktonic organisms for the identification