"This phenomenon of metamorphosis as liberty saturates the imagery of the tales and the language in which they are conveyed; the animal disguise of the heroine equips her to enter a new territory of choice and speech; the apparent degradation works for her, not against her. Being a beast - a she-bear - can be preferable as a temporary measure to the constrictions of a woman's shape."
I find the middle stage of the stories, where the heroine is outcast and not her self, very interesting. It seemes to have a connection to the fur- and feather-like objects I'm making. They too suggest shape-shifting, disguise, enchantment and some sort of riddle. Something that is not what it looks like, feathered yet not feathered, animal yet not animal.
Another fairytale related thing I came across recently is the Telling Tales exhibition at the V&A museum. The online presentation is very good and almost substitutes for a real visit.