Hi guys and gals - was wondering if any of you have read a sci-fi book about a girl who can travels dimensions from earth through rings that only a select portion of people can see - in each world people transform into (in the lava world) umm i think big blue bear/lizard thing, in the water world, mer-people - umm the only other things I can remember about it is that she was a bigger lizard thing than normal, and a smaller mer-person than normal (everyone else conserved mass) oh and she was an orphan -

i know - jumbled mess of memories - but i loved the book back in the 70's

thanks!