| belemnoid |
A group of extinct cephalopod molluscs with an elongate, tapering body and an internal shell. They probably looked rather like squid or cuttle fish. The rear part of the bullet-shaped, cylindrical shell is known as the rostrum and has a conical cavity in the wide end into which fits a small conical structure called the phragmacone. This is divided by septa and cut by a siphuncle.
출처: www.sedgwickmuseum.org/education/glossary.html
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