Each of these photographs is of a female Eastern Tiger Swallowtail.
The one on the left is the normal yellow form, while the one on the
right is the black form. The black form is easily confused with the
Black Swallowtail. Instead of having yellow spots
on the thorax and abdomen (Black Swallowtail), there is a yellow line
on both sides of the body. 8/17/14 (Wolf. Oesterreich)