Assertion: early cephalopod | /r/CapableOf | creep along the seafloor
Facets:
Source sentences:
text: However, Plectronoceras and other early cephalopods crept along the seafloor instead of swimming, as their shells contained a "ballast" of stony deposits on what is thought to be the underside, and had stripes and blotches on what is thought to be the upper surface.