The rules governing correct behavior in the underground “subway”
systems of our great cities (particularly the New York subways)
are, however, much more simple and elemental than the etiquette
for surface cars. In the subway, for example, if you are a
married man and living with your wife, or head of a family, i.
e., a person who actually supports one or more persons living in
(or under) his (or her) household on the last day of the
preceding calendar year, provided that such person or persons
shall not on or before July 1 or if July 1 shall fall on a Sunday
then on the day nearest preceding July 1, himself (or themselves)
have filed a separate report as provided in paragraph (g), you
should precede a lady when entering, and follow a lady when
leaving, the train.