The adder or asp is one of the few named snakes to appear in heraldry, normally the generic term serpent is used. They can appear tied in knots but also in a more lifelike pose! A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Adder We might suppose that it shares with the serpent the meaning of “wisdom”. The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P101