Possible Essex Skipper
I came across this butterfly on my deck today. I have never seen it before, but looking for similar images, Wikipedia lists the Large Skipper, Small Skipper and the Essex Skipper. The first two weren't listed with a range in North America. Is it an Essex?
Bucks County Pennsylvania butterflies
I am not an entomologist, but to the best of my knowledge this is one of the grass skippers or a Sachem skipper, possibly a female. Remember that many butterflies and moths have slightly different patterns for males and females, and the pattern you saw on the tops of the wings can be very different than what you see if wings are folded up together.
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