In female golden hamsters, vomeronasal organ removal disrupts the elicitation of lordosis by lumbosacral tactile stimulation. A similar disruption occurs if the nasopalatine ducts are closed, without removing the vomeronasal organ. Injection of luteinising hormone-releasing hormone reverses the effect of vomeronasal organ removal. These findings suggest that chemosensory signals from the male hamster act via the accessory olfactory system, to facilitate the triggering of lordosis by somatic stimulation.