As the females are very heavy with eggs, they usually remain where they are.  After mating they begin almost at once to deposit their eggs, and do not take flight until they have finished.  The eggs are round, having a flat top that becomes slightly depressed as they dry.  They are of pearl colour, with a touch of brown, changing to greyish as the tiny caterpillars develop.  Their outline can be traced through the shell on which they make their first meal when they emerge.  Female Cecropas average about three hundred and fifty eggs each, that they sometimes place singly, and again string in rows, or in captivity pile in heaps.  In freedom they deposit the eggs mostly on leaves, sometimes the under, sometimes the upper, sides or dot them on bark, boards or walls.  The percentage of loss of eggs and the young is large, for they are nowhere numerous enough to become a pest, as they certainly would if three hundred caterpillars survived to each female moth.  The young feed on apple, willow, maple, box-elder, or wild cherry leaves; and grow through a series of feeding periods and moults, during which they rest for a few days, cast the skin and intestinal lining and then feed for another period.

After the females have finished depositing their eggs, they cling to branches, vines or walls a few days, fly aimlessly at night and then pass out without ever having taken food.

Cecropia has several `Cousins,’ Promethea, Angulifera, Gloveri, and Cynthia, that vary slightly in marking and more in colour.  All are smaller than Cecropia.  The male of Promethea is the darkest moth of the Limberlost.  The male of Angulifera is a brownish grey, the female reddish, with warm tan colours on her wing borders.  She is very beautiful.  The markings on the wings of both are not half-moon shaped, as Cecropia and Gloveri, but are oblong, and largest at the point next the apex of the wing.

Gloveri could not be told from Cecropiain half-tone reproduction by any save a scientist, so similar are the markings, but in colour they are vastly different, and more beautiful.  The only living Gloveri I ever secured was almost done with life, and she was so badly battered I could not think of making a picture of her.  The wings are a lovely red wine colour, with warm tan borders, and the crescents are white, with a line of tan and then of black.  The abdomen is white striped with wine and black.

Cynthia has pale olive green shadings on both male and female.  These are imported moths brought here about 1861 in the hope that they would prove valuable in silk culture.  They occur mostly where the ailanthus grows.