Below you see what appears to be a somewhat worn Clouded Sulphur butterfly on a wild aster yesterday. This little yellow butterfly (Colias philodice), also called a Common Sulphur, is probably enjoying its last days on earth. It derives its name from the yellow chemical sulfur (spelled sulphur in British English). It and other butterflies that are yellow (like butter) may also be the origin of the term “butterfly.”
The literature indicates that the female Clouded Sulphurs probably have laid their eggs by now and that the caterpillars should have emerged from them or be emerging. These caterpillars reportedly will hibernate over the winter until the spring. (Image taken in Brooklin, Maine, on October 3, 2022.)