Assertion: coccyx's surface | /r/HasProperty | marked by transverse grooves
Facets:
Source sentences:
text: The posterior surface is convex, marked by transverse grooves similar to those on the anterior surface, and presents on either side a linear row of tubercles–the rudimentary articular processes of the coccygeal vertebrae.
text: The anterior surface of the coccyx is slightly concave and is marked with transverse grooves that indicate the junction of the vertebrae.