It would be punctuated like this: <em>The Atlantic Monthly.</em>
You would <em>not</em> put it in quotation marks. That is for smaller literary works. A <em>magazine</em> title would be in italics only. Here's a few sources supporting this.
Duvitch family is the protagonist of the story. They are narrated the most important ones. The Duvitch family is the main aspect and conflicted in the story. There is a begining and improvment in the end to their characters.