According to a Web search, a mature seed head of Queen Anne’s Lace will close up upon itself to form a bowl looking somewhat like a bird’s nest. I captured this one before it turned a brownish color, another reason why it also is called Bird’s Nest Plant.
An important side note: Queen Anne’s Lace is host to the Black Swallowtail butterfly, which could account for it being one of the few common large butterflies left.
Sheila T Illustrated© 
Very beautiful butterfly!
Appreciate your visits and your compliments, Ilex!!