Assertion: horseshoe crab's pair | /r/AtLocation | the underside of the prosoma
Facets:
Source sentences:
text: On the underside of the prosoma, six pairs of appendages occur, the first of which (the small pincers or chelicerae) are used to pass food into the mouth, which is located in the middle of the underside of the cephalothorax, between the chelicerae.