3.后肾( metanephros) Mesonephric duct Urachus Mesonephric duct Blade Metanephric y Renal pelvis Ureter Cloaca Cephalic aror caly? Buds of arched Renal Primary straight d collecting Metoneph tissue Caudal major calyx Develop minor calyces FG. 17-8 Later changes in the development of the metanephros3.后肾(metanephros)