Reference has been made to a legend from McHenry County, Illinois of the Bull Valley Monster. Not much is available in print but there are several references on the net.
Arlington Heights.org – “I am married to the Bull Valley Monster.  The Monster “died” in ’65 when he went to Viet Nam. He did his “scares” near Hamburger Hill in Bull Valley around Chester Gould’s place (creator of Dick Tracy).”
“Ah yes, Cuba Road and the famous Bull Valley monster! ”
“the Bull Valley Monster was one of the legends I was thinking about! Get the Monster on here! ”
“Mystery of the Bull Valley Monster solved! ”
Campfire Soapbox – “When we were teens and would take others out for a night of hunting snipe, we would also make sure, once they got out of the car, that they understood the lurking danger of the Bull Valley Monster!”
Chicago Tribune – “Maybe it was the parties where guests purportedly dressed in flowing robes, the collection of unusual artifacts or the persistent rumors of a “Bull Valley Monster” seen lurking there.”
Eons – “We have one up here in Northern Il the Bull Valley Monster.”
Fortean Times – “Unless it was the Bull Valley monster. Tall, lumbering, hairy, and drawn to cars parked on the side of the lonely roads that ran through Bull Valley. If your doors weren’t locked he’d pull you out and pick your arms off like the wings off a fly.”