Before the tea kettle Malfoy graciously filled with the tip of his wand was even steaming, they both jumped at the sudden appearance of a bright, wispy bit of smoke charging into the tent. It might have been a long time since she'd actually seen one, but Hermione recognized a patronus when she saw one. Whatever it was dissipated before she got a good look at the form. She'd been so startled that she hadn't even had the presence of mind to determine the shape.