Whistler and his butterfly
No one knows when James McNeill Whistler first used the butterfly as a signature in his paintings and prints. By the 1870's it had become a very important element in his works and he even used it as a decoration and signature on letters, notes and invitation cards. The butterfly symbol became so popular that people used to bring back paintings they had purchased before he started using the symbol so he could paint in on the ones they owned.
Whistler liked the effect of the butterfly because it resembled ideographs used in oriental works of art. (What is an ideograph? An ideograph or ideogram is a character or symbol which represents an idea or thing. Examples: $, %.)
Whistler used his butterfly both as a symbol for himself and as part of the design in his paintings and prints. Over the years, the butterfly design changed from simple to very complex and sometimes, Whistler added a stinging tail.