みゆきぬしかいじゃありませんでした
美之主貝じゃありませんでした
miyukinushi kaija arimasendeshita

Noun
Desu Copula

The polite, past negative form of びのすがい

1. It was not the beautiful master shell.; It wasn't the beautiful master shell.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana