Figure 1. Adult (upper tight) and pupa (lower left) of the white M hairstreak, Parrhasius m-album (Boisduval & LeConte). The adult's head and antennae are to the right. Cocking your head slightly to the left alows you to see the white "M" on the underside of the hindwing.
Credit: Andrei Sourakov, Florida Museum of Natural History