The European lynx has a fairly small head surmounted by two large ears finely edged with black. The interior is rather white, and a tuft of black hairs of about 1.57 inches (4 cm) crowns them. Wide sideburns surround the lynx's head, and its eyes are made up of white and black. Though it purrs like a house cat, its pupils are round when they contract. Its night vision is remarkable thanks to a cellular layer at the back of the eye, the “tapetum lucidum”, which reflects ambient light. The lynx comes out at nightfall and hunts until morning.