The muse gets all the press, but here’s a fact: Good writing involves obsessing over punctuation marks. It’s 1 a.m., you’ve got a 5,000-word piece due the next day, and for the last twenty minutes you’ve been deliberating about the use of a semicolon versus a period in a single sentence. (But should it be two sentences? Twenty-five minutes, thirty minutes … ) As a rule, the effect of all that obsession is subtle, a kind of pixel-by-pixel accretion of style. Once in a while, though, a bit of punctuation pops its head up over the prose, and over the prosaic, and becomes a part of a tiny but interesting canon: famous punctuation marks in literature.

I was reminded of the existence of this canon last month, while rereading Middlemarch, which contains what might be the most celebrated use of an em-dash in the history of fiction. That sent me to my bookshelves in search of other examples of remarkable punctuation. I wanted specific instances, so I ignored the slightly different category of books or authors closely associated with a given kind of punctuation. (Celine and his ellipses, say, or Emily Dickinson and her famous dashes.) Some forms of punctuation seem less marked out for fame than others; if anyone knows of a noteworthy comma, I’d love to hear about it. But what follows is a — well, what follows is a colon, which sets off a list, which contains the most extraordinary examples I could find of the most humble elements of prose:

1. The parentheses in Nabokov’s Lolita

“My very photogenic mother died in a freak accident (picnic, lightning) when I was three…”

The sentence goes on — for 84 more words, eleven commas, one colon, one semicolon, and another set of parentheses. But the reader, like Humbert Humbert’s unlucky mother, stops dead. Nabokov is a daredevil writer, and often a florid one, but what he shows off here is unbestable economy. Like the lightning inside it, this parenthetical aside is swift, staggering, and brilliant. It is also Lolita (and Humbert) in miniature: terrific panache containing terrible darkness.

2. The em-dash in George Eliot’s Middlemarch

“One morning, some weeks after her arrival at Lowick, Dorothea — but why always Dorothea?”

There we are at the beginning of Chapter 29, bopping along pleasantly on prose as becalmed as “Once upon a time” — when, out of nowhere, Eliot veers hard and pitches us out of the story. What’s remarkable about this em-dash isn’t just the narrative incursion (common in novels since at least Tom Jones), nor even the brazenness of the disruption. (Though that is startling. It was one thing, in the nineteenth century, to opine in one’s proper place, generally at the beginning or end of a chapter. It is something else entirely for a narrator to interrupt herself.) What makes this em-dash stand out is that it does formally what the rest of the book does thematically. Why always Dorothea? Why always one self? Why always one’s self? Enough of that, says Eliot, and hustles us off to Casaubon’s corner. That insistence on seeing beyond the self is, as I argue in this week’s issue of the magazine, the alpha and omega of Middlemarch.

3. The ellipses in T.S. Eliot’s “The Love Song of J. Alfred Prufrock”

Let us go, through certain half-deserted streets,

The muttering retreats

Of restless nights in one-night cheap hotels

And sawdust restaurants with oyster shells:

Streets that follow like a tedious argument

Of insidious intent

To lead you to an overwhelming question …

Oh, do not ask, “What is it?”

Let us go, and make our visit.

Okay, I concede: The most famous ellipses of all time is not in “Prufrock.” It is not in literature at all. It is in the text crawl at the beginning of Star Wars (“A long time ago in a galaxy far, far away …”), which I can’t read without hearing that crashing first chord of John Williams’s score, and which I admire even while wishing George Lucas had seen fit to include one more comma.

But we are here to talk about literature, and, in that domain, Eliot wins the ellipses game. Everything in “Prufrock” is elliptical: those meandering streets, the foglike cat (fog and cats: name me two things more evasive), the hundred revisions, the perfume-inspired digressions — and all this is to say nothing of the five other literal ellipses in the poem: “lonely men in shirt sleeves, leaning out of windows … ”; “asleep … tired … or it malingers”’ “I grow old … I grow old … ” — aging in those very pauses, it seems. But by far the most yawning chasm in the poem is the first one: What overwhelming question, Eliot? The candidate options, as I see it, are “What is the meaning of life?” and “Hey, so, would you maybe want to have dinner with me sometime?” Existential exposure, romantic embarrassment: Poor Prufrock, no wonder he trails off into that visual stutter.

4. The colon in Dickens’s A Christmas Carol

“Marley was dead: to begin with.”

That is the opening line of A Christmas Carol, although it is less like an opening than like a train car immediately running into another train car. The sentence would be unremarkable if it read, “Marley was dead, to begin with.” The colon would be unremarkable if the sentence read “To begin with: Marley was dead.” But as written, this sentence is insane, or anyway destined to foment insanity in the grammatically prissy. It has death, a dangling participle, and a wonderfully garrulous narrator with some kind of unmentionable Victorian-era disease: wandering colon. It is great.

5. The period at the end of Primo Levi’s The Periodic Table

“It is that which at this instant, issuing out of a labyrinthine tangle of yeses and nos, makes my hand run along a certain path on the paper, mark it with these volutes that are signs: a double snap, up and down, between two levels of energy, guides this hand of mine to impress on the paper this dot, here, this one.”

A Christmas Carol opens with a remarkable use of punctuation; The Periodic Table ends with one. Levi’s strange, lovely, mostly memoir-ish book includes everything from short stories to accounts of his imprisonment in Auschwitz to a subtle investigation of chemistry — both as a scientific discipline (he was trained as a chemist) and as the invisible infrastructure of the world. Each of its 21 chapters is named for an element; the last one is “Carbon,” the stuff of life, the stuff of us. In it, Levi traces the trajectory of a single carbon atom: blown on the wind, dissolved in the sea, migrating into a leaf, into one eye of a many-eyed insect, into a glass of a milk, into the human body, into the brain, guiding Levi to place at the end of the sentence at the end of the chapter at the end of his book its final, atomlike dot.