Career
Pfeiffer made numerous collecting trips to Hungary, Dalmatia, Bulgaria, and Persia. He published many scientific papers on Rhopalocera in Mitteilungen der Münchner Entomologischen Gesellschaft and with Osthelder edited Lepidopteren-Fauna von Marasch in türkisch Nordsyrien in the same journal. His collection of Palearctic and Nearctic butterflies is in the Munich zoological museum Zoologische Staatssammlung München.
