Quote Originally Posted by carlisleishere View Post
Could have had stuck shed on the end of the tail, causing it to die (hence the black tissue). If that's the case, just keep it clean and it should heal up ok.
This is most likely the case. When snakes get layers of stuck shed on their tails, it constricts the tip until the point it falls off. After this happens, keep the wound clean until it heals. I think most people would recommend a betadine solution.