Pearl Bordered Fritillary

Pearl Bordered Fritillary

Observation - Pearl Bordered Fritillary. Description: Or is it a Small PBF? I know that the view of the underside of wings assists in ID but the butterfly was not obliging. Comments greatfully accepted. What advice have you on ID between the two species

Or is it a Small PBF? I know that the view of the underside of wings assists in ID but the butterfly was not obliging.
Comments greatfully accepted.
What advice have you on ID between the two species