I'm trying to describe a certain frog. It found in from upstream to midstream of the rivers and the surrounding forests. The beautiful croaking sound of "fi fi fi fi" has been loved by people from ancient times, and this resembles a sound of a deer. It was commonly kept as a pet during the Edo period, and an instrument called Kajika basket was made to breed them. There is a great physique difference of genders, which the female is twice as large as the male.