Shaggy inkcaps are edible but guides give you dire warnings about confusing the shaggy version with the Common Inkcap - also known as the 'Alcohol Ink Cap' because of its unfortunate effect (i.e. making you ill) when consumed with booze.
It is important to use caution if this mushroom is to be eaten or if the persons selecting this mushroom are unsure of the variety of Ink Cap being considered. As a cousin to the Shaggy Ink Cap, the Common Ink Cap, Inky Cap, or Alcohol Ink Cap mushroom as this type is also referred, it is a mushroom that can be toxic if eaten with or after consuming alcohol.
Of course ink cap mushrooms got their name from the fact that the mature heads (which have very black gills under a shaggy white top - producing another nickname of 'lawyer's wig') were boiled down to make ink.
Rest assured, dear reader, that I didn't eat this specimen - it was on its own and another foraging beast had already taken a big nibble! So I left it for that beast's second course.