substage of immediately preceded by oogenesis developmental stage oogenesis stage S11 oogenesis stage S12 FlyBase_development_CV FBdv:00005274 Oogenesis stage that begins when dying nurse cells form an anterior cap to the oocyte. Shortly after this, nurse cell dumping and growth of the oocyte are complete. Elongation of the dorsal appendages and formation of the innermost chorionic layer and endochorion begins during this stage. Temporal ordering number - 10160.