Obsession pays off once in a while. I believe that I may have identified Jim. Except I'm changing her name (and gender) to Annabelle, in honor of her likely species, Vanessa annabella. Now tell, me doesn't this picture look like our mysterious friend, right down to the three yellow bands? (Scroll past the butterflies to the "young larva" picture.) While you're there, check out those beautiful butterfly eggs, only imagine that they're a gorgeous glowing blue. That's what our Painted Lady eggs looked like under the microscope.
Annabelle will be a beautiful butterfly. She'll look just like our Painted Ladies, except she'll have white at the bottom of her wings instead of orange. Lovely.
Species detail for the West Coast Lady butterfly, aka Vanessa annabella, right here at Butterflies and Moths of North America.