Spot the difference: Damien Hirst's Gagosian paintings – in pictures

Methoxyverapamil (1991) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Controlled Substances Key Painting (Spot 4a) (1994) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Levorphanol (1995) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Iminobiotin Hydrazide (1995-96) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Bromchlorophenol Blue (1996) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Famotidine (2004-11) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Eucatropine (2005) Photograph: Damien Hirst/Science Ltd/Gagosian Gallery Urea-13C (2001) Photograph: Mary Altaffer/AP Another shot of Urea-13C Photograph: Timothy A Clary/AFP/Getty Images A painting reflected in the floor of the Gagosian New York show Photograph: Timothy A Clary/AFP/Getty Images Hirst himself in New York, in front of Minoxidil (2005) Photograph: Timothy A Clary/AFP/Getty Images Photograph: TIMOTHY A. CLARY/Timothy A Clary/AFP/Getty Images