I just found the answer to what these were called. In Stories in Stone a Field Guide to Cemetery Symbolism and Iconography by Douglas Keister he has a section on the evolution of the Death Head which is now called a Soul Effigy. He even has photos to go along with the section to show how the Death Head went from a skull and bones to an angel head with wings.
My Original Post
If you haven't read this book it is a great book that every cemetery wander should own a copy.