Tubular horn that is produced by the terminal papillae of the dermal lamellae of the inner hoof wall (stratum internum or stratum lamellatum). Terminal horn fills the 'gaps' between the horny lamellae between the end of the dermal lamellae and the solar surface of the hoof and, therefore, forms a part of the white line. The striations visible in the white line are caused by alternating leaflets of lamellar horn and terminal horn.