From malaco- ("soft") + Ancient Greek ὄστρακον (ostrakon, “shell”).
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Malacostraca Sentence Examples
The science of insects began with Aristotle, who included in a class "Entoma" the true insects, the arachnids and the myriapods, the Crustacea forming another class ("Malacostraca") of the "Anaema" or "bloodless animals."