The need for unimpeded vision and good hearing was particularly acute for cavalrymen, therefore this type of helmet was used primarily by mounted troops.
An excellently-preserved example of a Boeotian helmet, which may have belonged to one of Alexander the Great's cavalrymen, was recovered from the Tigris River in Iraq, and is now in the Ashmolean Museum.
In the late Hellenistic period, the helmet evolved into a type with a taller, more conical skull and often a reduced brim.
On the altar of Gnaeus Domitius Ahenobarbus (a consul in 122 BC), a Roman cavalryman is depicted wearing it with the later more conical skull and furnished with a falling horsehair plume.
The naming conventions and typology of ancient helmets are largely of modern origin and do not reflect contemporary usage.