The Warbling Sea Shell (Season 2, Episode 2)

The Warbling Sea Shell is the second episode of the second season of the anime, Mushishi Zoku Shou.

Synopsis
A girl whose father is isolated from the village on the coast has become weirdly speechless. Her father didn't allow her to talk to other villager's children, but she made a strong friendship with the village chief's daughter.

However that didn't close the case, because when that Mushi is seen on the beach, it means a disaster will come.