All three order a beer. As they are about to have a swig of beer, all of them notice 3 flies performing a swan dive in each of the 3 seperate beer mugs
The US officer curses in disgust and asks the bar keeper for another beer. The Brit calls his US buddy a wuss and takes the fly from his glass and flicks it to the floor while drinking his beer.
The Canadian looks at the fly in his glass and says "son of a b....!" He then takes the fly from his drink and places it at the edge of his mug and while tapping the fly on its back he shouts "SPIT IT OUT, SPIT IT OUT"
