ABSTRACT: In this paper, we compile the plankton tow and sediment trap data previously obtained in the North Pacifi c and discuss the relevant results for ten representative radiolarian taxa. Didymocyrtis tetrathalamus and Tetrapyle octacantha group are controlled by warm water currents. Tetrapyle octacantha group is a Tropical-Subtropical indicator whose living zone is broader than that of D. tetrathalamus. Pseudocubus obeliscus is a productivity indicator. Spongotrochus glacialis appears to be advected from the Subarctic Current through the California Current into the central Equatorial Pacifi c. Pseudodictyophimus gracilipes, Stylochlamydium venustum, Larcopyle butschlii, and Litharachnium tentorium show distributions conformable with the “tropical submergence” hypothesis. Botryostrobus aquilonaris and Stylodictya aculeata seem to be associated with upwelling and we defi ne them as “upwelling” taxa.