Normally I don't bother too much with fungi. Too many, too complicated, no really good field guide that I know of (although Rogers Mushrooms is useful).
But Stinkhorns are so extraordinary looking that I made an exception and photographed this little group in the Brenne in late May. Their scientific name, predictably, is Phallaceae, and this one I think is Common Stinkhorn Phallus impudicus. They supposedly give off a stench like rotting meat, but I think it varies a lot and I can't say I noticed it. In any event, the olive green slime on the cap is there to attract flies which normally visit carrion and manure.
The Mushroom Expert is well worth reading on the subject and even has a Stinkhorn Hall of Fame. Apparently he gets more questions about this group of mushrooms than almost any other. People are very concerned about smelly rude things popping up overnight in their gardens.