ほそうみになでわありませんでした
細海蜷ではありませんでした
hosōmini nadewārimasendeshita

Noun
Desu Copula

The polite, past negative form of ほそうみにな

1. Was not a fine, small seashell.; Was not a delicate, curled seashell.

Past/Perfective
Negative
Polite
Formal Register
Usually Written in Kana