Just as there is a spell to force animal-form animagi to turn human again, there is also a spell to do the reverse; this version is much less commonly known or used, of course, but it does exist. With another quick cast, Skeeter morphs into the ugly little beetle Harry remembers very clearly. He scoops her up into the jar and seals it shut, though of course is benevolent enough to make sure she has adequate airflow. He’s not here to kill her, after all.