When I was little my mother bought for me two lore books for the Harry Potter universe

One was Quidditch Through The Ages

The other which I ironically forgotten the name of (ironic because I enjoyed it so much more) was a bestiary that talked about the creatures of the universe. Many that weren't seen in the books.

I remember there was this one creature said to be a wizard family transformed into spider like maneaters by a rival wizard family. Who ate the rivals as payback but realized there was no one left to hold a wand to change them back.

I have fond memories of these books and want to know if anyone here knows what I'm talking about and if they had copies.

Strangely I've never heard anyone speak of these lore guides.