Tales about frogs. Starting with two equal opportunity sections: frog princes, and frog princesses. With their differing plots.
And then a section on the frog wooing a mouse tales, and another on more various tales from myths to fairy tales where the frog is just a helper, to animal tales. Finally, a section of frog fables.
I particularly liked the first two because of my interest in fairy tales, but certainly there's a great variety here. The frog princesses, unlike the the frog princes, seem to have gotten the literary treatment from the precieuses.
There are no tales in which the heroine frees the frog prince by a kiss, which is a modern innovation of uncertain origin. (There are older tales in which an enchantment is broken by a kiss, but not of a frog. This includes an example, where it's an dragon.)
Some fit the motif into quite different tales.