An illustrated reference set with seventy-two comprehensive entries in alphabetical order that describe all of the major groups of organisms that live in or near water.

v.1. Algae, bacteria, and protists-Barnacle -- v.2. Barracuda and relatives-Carp and relatives -- v.3. Catfish-Crab -- v.4. Deep-sea fish-Flying fish and relatives -- v.5. Frog and toad-Mudskipper and relatives -- v.6. Newt and salamander-Piranha and relatives -- v.7. Plankton-Sea anemone -- v.8. Seabird-Sea turtle -- v.9. Sea urchin and sand dollar-Sponge -- v.10. Starfish-Worm -- v.11. Index volume.