Description:
Dragonfly and damselfly oocytes regularly contain two nucleoluslike bodies of different sizes, a primary nucleolus and a secondary nucleolus. The primary nucleolus stains more deeply with RNA stains than with an arginine stain; the secondary nucleolus stains conversely. The primary nucleolus incorporates uridine under all conditions tested; the secondary, only after precautions have been taken to preserve soluble RNA. Both incorporate lysine.