Then I caught the patient’s eye and followed it, but could trace nothing as it looked into the moonlight sky, except a big bat, which was flapping its silent and ghostly way to the west. Bats usually wheel about, but this one seemed to go straight on, as if it knew where it was bound for or had some intention of its own.

– Bram Stoker

Dracula, Chapter 9. Renfield, the patient in the lunatic asylum, becomes agitated and attempts to escape but is caught by the orderlies and Dr. Seward. Just then Renfield looks upwards and Dr. Seward notices a large bat flying above. Renfield suddenly becomes calm and agrees to go back to the asylum. Seward is puzzled, he doesn’t realize that the bat is Dracula who can transform into an animal.