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“mesoplankton”
A plant or animal organism of intermediate body size, between macroplanktons, which are large, and microplanktons, that are very small: The mesoplankton thrive between about a hundred fathoms from the bottom of the sea and a hundred from the surface, or between the epiplanktonic and bathyplanktonic levels.
This entry is located in the following units:
meso-, mes-, mesi-
(page 7)
plankto-, plankt-, -plankton
(page 3)