The first series of ID Leaflets, edited by John A. Lindlay, was dedicated to plankton. It provides standard keys for the identification of the major phytoplankton and zooplankton species in the North Atlantic.
The second and latest leaflet series is dedicated to diseases and parasites of fish and shellfish. It provides diagnostic aids (in both English and French) for identifying the most important diseases and parasites of fish and shellfish in the North Atlantic and adjacent seas. The current series editor is Stephen W. Feist.
Both series are available online.
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