Assertion: brittle star's mouth | /r/AtLocation | its underside
Facets:
Source sentences:
text: The mouth of an asteroid is located on its underside.
text: The mouth is claw-like and is located on the underside; it has 5 tooth-like plates that point inwards and are called Aristotle's lantern.
text: Their mouth is situated on the underside and their anus on top (except feather stars, sea cucumbers and some urchins).