"... on the nose ... "

usually to do with gambling on horses - eg "A fiver on the nose" - meaning a five pound bet for a win.

(a fiver being a banknote - otherwise known as a lady godiva)

"A fiver IN the nose" generally has more to do with venezuelan and colombian exports.

Though usually it would be unlikely to be a fiver as that would undermine the associated image of decadent excess.

A pony is slang for £25

Hence the possible confusion caused at a horse race when a young cockney announces he'll bet "a pony on the nose" to his bookmaker of choice.

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