埋甕








埋甕（うめがめ）は、縄文時代の深鉢形土器を土中に埋納した施設。


縄文中期から後期にかけて関東平野や中央高地で見られる習俗で、縄文後期には中央高地では衰退し、関東平野では継続した。


埋甕は住居の内部（出入口部）に営まれる住居内埋甕と住居外に営まれる住居外埋甕があり、複数営まれる場合もある。土器は煤などが付着されていることから日常的に使用されているものが転用され、特に口縁部が平なものが選ばれる。正位または逆位で配置され、正位の場合は石蓋があることもあり、口縁部や底部が破損または底部が意図的に穿孔されている。住居内埋甕は民俗事例などから乳幼児の埋葬施設や、幼児の健やかな成長を祈念し胎盤（胞衣）を埋納した胞衣壺であると考えられている（木下忠による）。内部の埋納物は例外的に土器や石器が含まれることがあるか明確に確認された例がなく、残留脂肪酸分析も行われているが胞衣が含まれているかは不確定である。


一方、住居外埋甕からは乳幼児のものも含む人骨の出土例がある。縄文時代の墓は土坑墓や土器棺墓、石棺墓などが一般的で、墓所は集落内に設けられた墓域や廃絶住居、貝塚などに営まれるが。被葬者の死去直後の一時埋葬と一定期間を経た二次埋葬があり、住居外甕は再葬墓である可能性も考えられている。







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