Task: Question Answering
Input (English): Passage: Leon Bismark "Bix" Beiderbecke (March 10, 1903 – August 6, 1931) was an American jazz cornetist, pianist, and composer.
Beiderbecke was one of the most influential jazz soloists of the 1920s, a cornet player noted for an inventive lyrical approach and purity of tone. His solos on seminal recordings such as "Singin' the Blues" and "I'm Coming, Virginia" (both 1927) demonstrate a gift for extended improvisation that heralded the jazz ballad style, in which jazz solos are an integral part of the composition. Moreover, his use of extended chords and an ability to improvise freely along harmonic as well as melodic lines are echoed in post-WWII developments in jazz. "In a Mist" (1927) is the best known of Beiderbecke's published piano compositions, and the only one that he recorded. His piano style reflects both jazz and classical (mainly impressionist) influences. All five of his piano compositions were published by Robbins Music during his lifetime.
A native of Davenport, Iowa, Beiderbecke taught himself to play the cornet largely by ear, leading him to adopt a non-standard fingering technique that informed his unique style. He first recorded with Midwestern jazz ensemble The Wolverines in 1924, after which he played briefly for the Detroit-based Jean Goldkette Orchestra before joining Frankie "Tram" Trumbauer for an extended engagement at the Arcadia Ballroom in St. Louis, also under the auspices of Goldkette's organisation. Beiderbecke and Trumbauer joined Goldkette's main band at the Graystone Ballroom in Detroit in 1926. The band toured widely and famously played a set opposite Fletcher Henderson at the Roseland Ballroom in New York City in October 1926. He made his greatest recordings in 1927. The Goldkette band folded in September 1927 and, after briefly joining bass saxophone player Adrian Rollini's band in New York, Trumbauer and Beiderbecke joined America's most popular dance band: Paul Whiteman and his Orchestra. 
Question: What is the last name of the leader of the band that the musician with demonstrate a gift for extended improvisation joined in the Graystone Ballroom?
Output (English): Goldkette.