Assertion: sea urchin's development | /r/HasProperty | embryonic
Facets:
Source sentences:
text: This use originated in the 1800s, when their embryonic development became easily viewed by microscopy.
text: This use originated in the 1800s, when their embryonic development became easily viewed by microscopy.
text: This use originated in the 1800s, when their embryonic development became easily viewed by microscopy.