also being a ratsnake a corn would have keeled scales which makes them appear shiny in sunlight and makes them feel rough when held.Keels are ridges up the middle of each scale.king and milk snakes are smooth scaled.This also a good way to tell black racers and black rats apart.racers are smooth scaled dull black on back and solid grey underneath.black rats are shiny black,mottled cream and grey belly underneath with white chin.head scalation in both are totally different as well as species temperment.I never met a racer that liked me or anyone else for that matter.rats are more congenial and much more likely to fe found off the ground.Racers are named that for a reason,rats tend to move slower or rely on stillness to go unobserved.