Absence of a third or a fourth premolar or of one molar.

缺少一个第三或者一个第四前臼齿或者一个臼齿。

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But Longgupo also yielded a mystery jaw fragment, including the fourth pre molar and the first molar.

但龙骨坡还发现了一件神秘的下颌残片，包括第四前臼齿和第一臼齿。

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Unfortunately, the fourth premolar in the upper jaw is quite large and looks like the first molar in the lower jaw; it is known as a carnassial tooth.

不幸的是，上颚的第四颗前臼齿很大，看起来就象是下颚的第一颗臼齿，这颗前臼齿也被称作叫裂齿。

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