Complex sentence: Asbury's book described the Bowery Boys, Plug Uglies, True Blue Americans, Shirt Tails, and Dead Rabbits, who were named after their battle standard, a dead rabbit on a pike.
Split into simpler sentences: Asbury's book described the Bowery Boys, Plug Uglies, Shirt Tails, and the Dead Rabbits. The last were so named after their battle standard, a dead rabbit on a pike.