On Questlove’s list of his favorite 50 hip-hop songs, he offers an important caveat. “I decided to concentrate on 1979-1995,” he writes, because the latter year marks the major label debut of his group the Roots and their second album, Do You Want More?!!!??! “I wanted to concentrate on the period that I was not professionally involved in the art form.” His canonical picks skew heavily toward the “golden age” of East Coast hip-hop, with a few cursory nods at the West Coast (one track apiece from NWA, Ice Cube and Dr. Dre, but no Ice-T or 2Pac) and the South (Geto Boys, but no OutKast or bass music). Questlove may not be much of a hip-hop historian — inexplicably, he ranks Rob Base & DJ E-Z Rock’s “It Takes Two” over Mobb Deep’s “Shook Ones Pt. II,” and doesn’t find any space for Nas (or Jay-Z, whose debut single “In My Lifetime” dropped in 1994). But he’s an engaging writer, and his capsule explanations for his picks are frequently entertaining, whether it’s humble-bragging how Chuck D gave him an extra copy of Son of Bazerk’s Bazerk Bazerk Bazerk, effusing about Trouble Funk’s “Pump Me Up,” or using Grandmaster Flash & the Furious Five’s “The Message” to talk about being unfairly pulled over by the cops in 2008. “It is like a jungle, still,” he writes about the latter.