Hugh Hopper, bassist for progressive rock group Soft Machine, died June 7 of leukemia in Kent, England. He was 64.Hopper started out as the road manager for Soft Machine before joining the group, which melded fusion jazz and progressive rock. The band was part of the Canterbury scene, a group of bands from the British city of Canterbury. After playing on six Soft Machine albums, he left the group in 1973 and released a solo album “1984,” and recorded with a number of art-rock bands including a group led by Carla Bley. He reunited with other former Soft Machine members several years ago to form Soft Machine Legacy, which mixed original compositions with songs from the band’s heyday. He is survived by his wife, Christine, and two daughters.