These are eggs (nits) of the human head louse, Pediculus humanus capitis. They have an identical appearance to the eggs of the human body louse, Pediculus humanus humanus, but they are laid on hairs rather than clothing. The eggs of the crab louse, Pthirus pubis, are also laid onto hairs, but can be differentiated by their taller operculum, consisting of more than 1 cell layer. In contrast, the operculum of head louse eggs is only 1 cell layer tall.