A variety of it was invented for use in the Ring Cycle and is named for Wagner, and its first notable use in the orchestra saw it replace the ophicleide, itself a descendant of the serpent.
Bruce Broughton wrote a concerto for this instrument with Tommy Johnson in mind, and John Fletcher was the dedicatee of a concerto for this instrument composed by Edward Gregson.  It is featured as a soloist in the "Bydlo" movement of Pictures at an Exhibition, and near the end of his life, Vaughan Williams wrote an F minor concerto for it. A variety of it was invented for use in the Ring Cycle and is named for Wagner, and its first notable use in the orchestra saw it replace the ophicleide, itself a descendant of the serpent. For 10 points, name this cousin of the euphonium and basis for the sousaphone, the lowest-pitched member of the brass family.
Bruce Broughton wrote a concerto for this instrument with Tommy Johnson in mind, and John Fletcher was the dedicatee of a concerto for this instrument composed by Edward Gregson.  
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