a conical calcareous fossil tapering to a point at one end and with a conical cavity at the other end containing (when unbroken) a small chambered phragmocone from the shell of any of numerous extinct cephalopods of the family Belemnitidae.

 
  • 乌贼的化石,圆锥形石灰质化石,许多灭绝的头足类动物。
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