The strong resemblance which many of the yellow under-wings, as these moths are called, have to each other, has rendered their synonomy somewhat complex and confused. The species just decribed has been thought not to be specifically distinct from the Linnean Ph. paranympha (figured by Roesel, iv. pl. 18, figs. 1, 2), but it is of much larger size, the wings are more evidently dentated, the outermost black bar on the under wings is uninterrupted, and the inner one is not recurved anteriorly and continued along a portion of the abdominal margin. It is likewise nearly related to Catocala affinis (West. Drury, vol. i. pl. 23, fig. 6), which is a native of New York, but is at once distinguished from that species by its yellow abdomen, and having a yellow space along the margin exterior to the black band on the under wings.
