A leg of salmon is usually used as a joke in the work place and is generally used to test the gullibility of a new employee. It starts off by the manager or someone of senior authority asking the unsuspecting employee to carry out a personal favour for them. In this case the boss has asked the new employee if he/she minds going to the fish mongers to collect the leg of salmon that the boss had ordered earlier. Wanting to impress his/hers new boss the new employee (not giving a second thought of what he/she has been asked to do) willingly obliges to go on the errand only to be told by the fishmonger (in the tone of 1+1=2) that salmon don't have legs and return back to their place of work (usually to be greeted by hysterical laughter) looking as pink as a salmon.

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