The skull is cetacean-like but its jawbones lack the enlarged space that is filled with fat or oil and used for receiving underwater sound in modern whales.
它的头骨与鲸类相似，但它的下颚骨没有现代鲸鱼用来接收水下声音的、充满脂肪或油脂的扩充空间。
2
Notice how the original jawbones interlock to form sturdy walls.
请注意下颚骨是如何联锁而形成坚墙的。
3
Collectors pay thousands of dollars for the jawbones of a shark.