California Sisters (Adelpha bredowii californica) are more commonly associated with oak woodlands, so these butterflies don't show up on Bodega Head very often. These photographs were taken in Sebastopol on 18 October 2013.
Not only are there dramatic orange spots at the tips of the forewings, but note the smaller orange spots at the inside corners of the hindwings, the orange eyes, and the orange proboscis (see below)! The color scheme is a good match for a pumpkin patch in October!
P.S. I was wondering why these butterflies are called "sisters." It sounds like the genus is known for those strong white stripes running across the dark wings, a pattern which reminded someone of a nun's habit.