How does Wharton represent the custom of the different classes in "The Custom of the Country"?

In The Custom of the Country, Edith
Wharton presents the dynamics of the "who is who" in New York society at the beginning
of the 20th century.

The title of the novel The
Custom of the Country is allegorical to the saying "When in Rome, do as the
Romans". In this case, "the custom" referred to the comings and goings of the ruling
families of early New York City. The worth of each family was measured according to
their connections to the founding families of what once was New Amsterdam. Therefore,
the closest the family was to its dutch roots, the more "pure" its pedigree would
be.

From the story, we learn that these families had a
tendency to marry amongst themselves, and most of the marriages were to preserve their
lineage as well as to continue the control that they exercised in parts of the city. In
the story, we see the importance that these families exuded among the common folk, and
how they would snub people outside of their immediate circle. In order to be able to
enter the circle you had to either have money or be a part of the inner sanctum of the
old country families. They also had a tendency to do everything in groups. When they
were not all together in one group, they would divide into subgroups that will
eventually meet up together again. They all kept tabs on each other, as well. It was
like being part of a huge family whose links were heritage and
wealth.

Undine Spragg, the main character, came from what
could have been classified as "upper class" in the Midwest. However, nothing prepared
her for the amount of courtesies and traditions that were so important to the society of
New York. She basically had to change completely, including the way she dressed, the
people with whom she mingled, and the manner in which she behaved among society in order
to be at least considered "fit" to be among the Dagonets and every other ruling
family.

In the end, Undine was never satisfied, which shows
the shallowness of her life. She did not really belong to the group she so desperately
tried to fit in. Nothing could ever please her. She was chasing waterfalls that
reflected the fantasies she created about herself living the life of a New York
socialite. In order to follow the custom of the country, the first thing you need is to
be one of them. And she was not.