An American, an Englishman, and an Irishman

An American, an Englishman, and an Irishman are sittin' next to each other in a pub.
There is a fly buzzing around the American's beer that eventually lands on his glass.
The American sees the fly, gets a disgusted look on his face and asks the bartender for another beer.
The bar-keep obliges as the Brit has a bit of a chuckle to himself.
But, he stops his laughter when the fly lands in his own glass.
The Englishman looks at the American and winks, as he waves the fly away and then finishes the pint.
The fly then finds its way over to the Irishman's fresh pint, and lands on the rim.
Before it can even flap a wing, the Irishman grabs the fly by the back of its head and shakes it over his glass saying "Spit it out, ya lil fooker! Spit it out!"