An analysis is made of the abundance, vertical occurrence and taxonomy of calanoid copepods from 29 samples. The samples were obtained in the northeast Atlantic between approximately 30° and 60°N and at intervals from the surface to a depth of 5000 m.

The zooplankton is found to be more abundant in the upper 1000 m of the water column and below 2000 m the concentration is extremely small. The mean size of adult copopods is greater between 500 and 2000 m than in other depth intervals and the greatest number of species occurs in the upper 1000 m. Two new genera, 17 new species and the previously unknown males of three species are described and illustrated. Twenty-one other species are discussed and five species are reported for the first time from the Atlantic Ocean.