by Richie UnterbergerA middling late-sixties psychedelic group, Twentieth Century Zoo were the first such band from Phoenix to get an album released and nationally distributed, even if that LP was on a small L.A. label, and not many people would hear it. The band evolved from the Bitter Sweets, which had a couple of local singles in 1966 and 1967. In 1967 and 1968, Twentieth Century Zoo had a couple of singles on the small Caz label, the first of these, "You Don't Remember, " being respectable psych-punk in the mold of the Music Machine. 　　In late 1968, the group recorded an album in Los Angeles for Vault Records, Thunder on a Clear Day. Featuring elongated fuzz-sustain riffs and heavy organ, somewhat in the manner of Fever Tree, there was little to make it stand out from the crowd of similar late-sixties American albums. At times there was also a hard blues-rock feel, which could break into tedium on longer tracks, such as a ten-minute cover of Little Walter's "Blues with a Feeling." Twentieth Century Zoo got to open for several bigger bands in Phoenix, such as Iron Butterfly and Blue Cheer, and did one more single for Vault before breaking up in 1970. Their album was reissued by Sundazed in 1999, with non-LPs singles and outtakes tacked on as bonus tracks.