- Captain James T. Kirk: Were you hurt?
- Doctor McCoy: No, just surprised. It isn't every day a dinosaur falls on you.
- Doctor McCoy: My shoes are full of sand.
- Mr. Spock: Doctor, your lack of scientific interest is amazing.
- Captain James T. Kirk: The captain of a ship, no matter his rank, must follow the book.
- Mr. Spock: A capability, I'm afraid, out of the reach of most humans.
- Doctor McCoy: You Vulcans are the most impossible, unimaginative...
- Captain James T. Kirk: Bones, that's not helping the situation.
- Captain James T. Kirk: A forcefield. It seems harmless enough.
- Doctor McCoy: So do the bars of a jail unless you're on the inside.
- Captain James T. Kirk: And we are definitely on the inside.
- Mr. Spock: They appear to be as advanced beyond Earth civilization as you are from a colony of ants.
- Mr. Spock: [while searching the terrain] Captain, does it strike you strange that two such different ecologies could coexist so closely?
- Tom Markel: So far, Mr. Spock, we haven't found anything funny in this.
- Mr. Spock: Animals in a zoo rarely do.
- [last lines]
- Mr. Spock: I have just received their final telepathic message.
- Captain James T. Kirk: Which is?
- Mr. Spock: We'll be welcomed back in twenty or thirty centuries.
- Captain James T. Kirk: Our time or theirs?
- Mr. Spock: Theirs, and it will take me some time to figure out how long that is.
- Captain James T. Kirk: Either way, Mr. Spock, it will hardly be our problem.