Drawing of a pair of silkworm moths with the female laying eggs. OK, so technically this is a moth picture and not a butterfly picture but I think most of us use the terms interchangeably and call all of these types of insects butterflies.
These are the moths whose worms spin the cocoons that we make silk from. You could easily use this picture as is, use one of the moth drawings alone, or use the drawing along with our silkworm drawing.
The History of Insects was published in 1813 without identifying an illustrator. Which is truly a shame because the work is full of wonderful insect drawings like this one.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.