The feather, especially that of the ostrich appears with great regularity in the crests of a full achievement of arms, typically in the shape of a plume. Wade associates this device with “willing obedience and serenity of mind”. The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P74 They are much less common on the shield itself, unless part of an arrow, which may be feathered of a different colour, or a quill pen. A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Feathers