The kappa is named after the Japanese for ‘river’ (kawa) and ‘child’ (wappa). Written by Akamatsu Sōtan, Tonegawa zushi is an illustrated history of the Tone River. The book records the history and folklore of the communities found along the Tone. According to Sōtan, the river was believed to be home to the neneko kappa, illustrated here. With webbed claws and scaly skin, it was a dangerous creature that moved location every year, causing chaos wherever it went.