"The fly, my dear sir, has one striking feature: its wings are typical of the aerial powers of the psychic faculties.  The ancients did well when they typified the soul as a butterfly." 

- Renfield in Bram Stoker's Dracula Chapt. XX


Renfield:

          "He used to send in the flies when the sun was shining.  Great big fat ones with steel and sapphire on their wings; and big moths, in the night, with skull and cross-bones on their backs.'  Van Helsing nodded to him as he whispered to me unconsciously: -
        'The Acherontia atropos of the Sphinges - what you call the "Death's-head moth!""

- Dracula Chapt. XXI