Virginia Opossum - Didelphis virginiana - This is the best of a number of exceedingly poor photos of possums at my door. They come in the middle of the night to raid the cat food but hide under the stairs as soon as I try to open the storm door; and shooting with a flash through glass yields very unsatisfactory results. I was inclined to view them as purely a nuisance at first. But, in reading about them, I found that they are immune to the venom of pit vipers and prey on snakes. So, maybe it's worthwhile to have them around instead of copperheads and rattlers.