What Is the Primordial Pouch in Cats?

Just above the hock of your cat's hind leg is what is called the primordial pouch, which is a little flap of skin. Some cats have it and some don't. This flap is a remnant from when cats were wild. It is thought that the pouch may have served as a bit of a storage area or maybe even as a bit of a flap that protected their soft bits when fighting. But it serves no purpose for most domestic kitties.