Etymology and distribution of 七寸.

Nasu 【七寸】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Nagano-ken . A variant of the 古畑 . Nagano-ken Matsumoto-shi Marunouchi was in the Edo period in the clan of Matsumoto of the Clan Office. 古畑 Furuhata reference.

※ Nagano-ken Matsumoto-shi In Asama hot spring tells that in 961 (Yuwa's first year) he was named after Ishikawa-so in the southern part of Ishikawa-ken (Kaga). Location unknown.