Fall Webworm Caterpillars. I observed them closely in their web "tent" and did some online comparing and determined that this is the Species of Caterpillars I recently examined. They are small white Caterpillars that, in the late Summer of Fall, build a web "tent" on the end of the branch of a Hardwood Tree.
I intentionally ripped the side out of one of the tents, and the white Caterpillars quickly woke up and started crawling around. The next time I observed the tent, it had been fully repaired and the Caterpillars were dormant again - starting the Pupa stage in its lifecycle to become a moth. In fact, the name Fall Webworm actually refers to the Moth part of the lifecycle. The Moth's Scientific name is Hyphantria cunea.
They are considered a pest by some as they can damage a young or an unhealthy Tree.