Flies in the beer

An Irishman, an Englishman and a Scotsman go into a pub and each order a pint of Guinness. Just as the bartender hands them over, three flies buzz down, and one lands in each of the pints.
The Englishman looks disgusted, pushes his pint away and demands another pint.
The Scotsman picks out the fly, shrugs and takes a long swallow. The Irishman reaches into the glass, pinches the fly between his fingers and shakes him while yelling, “Spit it out, ya bas**rd! Spit it out!”