せたしじみじゃなかったです
瀬田蜆じゃなかったです
setashijimijanakattadesu

Noun
Desu Copula

The polite, past negative form of せたしじみ

1. Wasn't Setada-shijimi.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana