Judaspenning is a recurring theme in the oeuvre of Jan Mankes. At least 4 paintings feature it: Vaasje met Judaspenningen (1910), Dood vogeltje met judaspenningen, (1910), Keulse pot met reigersneb (1915) and this work. (see A. Mankes-Zernike, Jan Mankes, Wassenaar 1928, p. 57-62). For Mankes it referred to transitoriness. Combined with a dead bird or animal skull the paintings clearly form a Vanitas language.. http://www.invaluable.com/auction-lot/jan-mankes-dutch,-1889-1920-309-c-nkz64x52vh