Groucho, Harpo and Chico are shown below in Al Hirschfield’s original cover artwork for ‘Why a Duck?’, a profusely illustrated work about the Marx Brothers edited by Richard J Anobile and published in 1971.

Extracted from Antiques Trade Gazette | Ian McKay

A signed ink on board drawing, it made $20,000 (£15,660) in an Illustration Art sale held by Swann Galleries (25/20/12% buyer’s premium) of New York on December 6.

The book’s curious title commemorates a well-known gag in the first extant Marx Brothers film*, The Cocoanuts of 1929. In somewhat abbreviated form it runs as follows – Groucho: “…here is a little peninsula, and here is a viaduct leading over to the mainland.”

Chico: “Alright! Why a duck? Why that… why a duck? Why a no chicken?”

* No print survives of a much earlier silent film.