I Found A Large Brown Caterpillar That Has A Horn On Its Tail And What Appears To Be 4 Smaller Horns On It's Head. It Looks A Lot Like A Tomato Hornworm But It Has The Head Horns. What Is This Caterpillar?

I also found one on my persimmon tree, about five inch long with four pairs of curved horns on its head/thorax.  Its body is covered with short, black spikes and a short horn on its tail.  The horns are orange colored but have balck tip.  Searching the Internet for its identity, it appears that this hornworm is called hickory horned devil.  It is intimidating by appearance, but quite harmless, and has tenacious grips on its feet to dislodge it from the tree stem.