Assertion: sea urchin's spine | /r/MadeOf | additional ossicles
Facets:
Source sentences:
text: These spines are made from additional ossicles found in the body wall; instead of being fused with the ossicles of the test, these additional ossicles are elongated and articulate on called "bosses.
text: These spines are made from additional ossicles found in the body wall; instead of being fused with the ossicles of the test, these additional ossicles are elongated and articulate on called "bosses.