In unfertilized emu or ostrich eggs.
5 seconds sound clip from the Jurassic Park (1993) movie soundboard.
You can hear this line at 00:27:32 in the Blu-ray version of the movie.
Quote context
[...]
- Well, look here. Those hard-working cowpokes you see behind us...
- Are these characters auto-erotica?
- No, we have no animatronics here.
- Those people are the real miracle workers of Jurassic Park.
- In unfertilized emu or ostrich eggs.
- Wait a minute. How do you interrupt the cellular mitosis?
- Can't we see the unfertilized eggs?
- Shortly.
- Now a whole team of genetic engineers goes to work on...
- Can't you stop these things?
- I'm sorry. It's kind of a ride.
[...]