Many species of Lymantriidae show tremendous variation in coloration, and this species is no exception. Wear and tear multiplies the apparent variation and adds to the confusion. In most cases, however, the basic lines and spots can be discerned. See the wingless female below, little more than an egg sack.

Here we have an egg mass deposited on the silk of the female's cocoon, followed by a photo of a typical larva. The last two photos are of a wingless female who normally will not leave the cocoon surface after emerging from it. She doesn't need to go anywhere to mate. The release of pheromones draws males to her. She is little more than an egg sack. Her adult life will be spent in egg laying, probably within 24 hours.

Beside the corpse of the hollow caterpillar is the cocoon of an Ichneumon wasp measuring 5.5 x 3.0 mm. I thank Tony Thomas for identifying the parasitoid (Ichneumonidae, probably Campopleginae). A similar photo appears in the introduction to Wagner's guide to eastern caterpillars on page 23. The wasp developed within the caterpillar, consuming a considerable portions of its internal contents. It emerge to pupate, creating its cocoon in part with fecal matter. The caterpillar corpse was adhered to the wasp cocoon. I found this on the leaf of a milkweed plant in a large patch about 100 yards from my house.