It is the attendant of the god of the waters.

It has some of the qualities and energies of the dragon, it has the power of transformation.

In pictures and sculptures we are familiar with its figure, often of colossal size, as forming the curb of a well, the base of a monument or tablet.

Yet, whatever its form in literature or art, it is the later elaborated representation of ancient Animism which selected the tortoise as one of the manifold incarnations or media of the myriad spirits that populate the air.
Chief and leader of the four divinely constituted beasts is the Lung, Japanese Ri[=o], or Dragon, which has the power of transformation and of making itself visible or invisible.

At will it reduces itself to the size of a silk-worm, or is swollen until it fills the space of heaven and earth.