I collected some caterpillars from masses of matted leaves of sweetgum trees on 9/18/2010. One caterpillar had a green parasite smaller than 1 mm at that time. I didn't record what happened between that date and 9/29/2010 when I saw a whitish larva building a cocoon inside the loosely woven cocoon that the caterpillar had built. It was the parasitic larva which has grown to almost 10 mm. The adult emerged last nigth, 10/14/2010. I am not entering the dates in the data field because the cocoon was kept indoors.
Here is the caterpillar, presumably Pococera.

And here is a video of the life cycle. It is possible to see the larva spinning its cocoon and later on the pupa wiggling and wriggling and rolling over. I had no idea that pupae could be so active.