Assertion: mollusk's shell | /r/Synonym | test
Facets:
Source sentences:
text: Sea urchins have a shell called a test, which comes in colors as varied as black, green, brown, purple and red.
text: Foraminifera and coccolithophores create shells known as "tests" which are made of calcium carbonate.
text: The shells of sea urchins are called "tests", and the moulted shells of crabs and lobsters are exuviae.