Clarion (heraldry)

The clarion (also clarichord, clavicord, rest or sufflue), is a rare charge in heraldry of uncertain meaning and purpose. It originates from England and is still largely exclusive to that country, though latterly it has been imported to other Anglophone nations. In Canadian heraldry, it is the cadency mark of a ninth daughter. 
It is generally said to represent a kind of wind instrument such as a panpipe or recorder, but does not resemble the trumpet-like clarion known to modern musicians. It may also be intended as an overhead view of a keyboard instrument such as a spinet. Alternatively it has been said to represent a 'rest', a device used by mediaeval knights to support a lance during jousting. In his "Display of Heraldry" John Guillim suggests that it may be a rudder. 'Clarion' is also the name given to a stop on an organ which imitates the sound of a trumpet.
A verse of poetry published in 1568 does not do much to clarify the issue: