In the mid-1800s societal behavior, in Europe, was a key indicator of one's class. In the Henry James novel, Daisy Miller, the main character, Daisy Miller, is American and is at odds with European societal norms. James' novel is a "study" of the character Daisy Miller, as seen through the perspective of the character Winterbourne, an American European gentleman. Daisy's continued spontaneous behavior spurred by emotional choices sets her teetering on the edge of expulsion from European high society. During the course of Winterbourne's "study" of Daisy, we learn how Mrs. Costello, Winterbourne's aunt, a member of the European high society, views Daisy's behavior. She warns Winterbourne of Daisy's spontaneity and disregard for ritual behavior, by referring to it as "uncultivated" (James, 21). This comment, so early on in the story line, immediately distinguishes class boundaries through behavior, and excludes Daisy from high society marking her as "common." At another point in the story, after learning about more of Daisy's free and emotionally driven behavior with multiple men in Rome, Mrs. Costello refers to the Millers' as whole entity, solely based on Daisy's behavior, as, "hopelessly vulgar" (James, 41). This comment functions as reinforcement of class boundaries based on behavior, again marking Daisy as "common." Mrs. Walker is another character who is member to the European high society, and who also condemns Daisy's spontaneous, risky behavior. When Daisy is going to meet an Italian gentleman, Mr. Giovanelli, outside the Colosseum, Mrs. Walker tries to caution her against this and pleads with Winterbourne to, "[not] let the girl ruin herself" by allowing people to see her making such a poor, "common" choice (James, 53). This portrayal of Daisy's blatant disregard for proper high societal behavior further works to show her behavior as a vital determiner in the establishment of her place in "common" class.