Brontosaurus
Huge beast. Ate only plants, but could crush a '93 Cabriolet with a single step of its titanic brontosaurus feet. Name means "Thunder Lizard" which is about as cool as you can get. Its only real drawback is that it didn't really exist. B+

Apatosaurus
This is what they're calling brontosauruses these days. Apparently they had some problem with the wrong skull on the wrong body--duh--and once they figured it out they had to change the name to "apatosaurus," which means "Deceptive Lizard." Personally I think they should have looked up the Latin for "Stupid Scientist." D

Dimetrodon
Looks like a gecko with a mohawk. Big sail on its back that they think attracted mates or conserved body heat. Actually, that's what scientists say about anything on an animal they don't understand. They could find evidence of an iguanadon with a ZZ Top beard and they'd say "the beard was probably to conserve body heat or attract mates." Which, come to think of it, is probably what ZZ Top uses them for. Anyhow, C

Tyrannosaurus Rex
Cool animal. Name means "Tyrant Lizard King." Cool. I wish my name meant "Tyrant Lizard King." Anyhow, we all know what makes this such a great dinosaur--it could completely eat you. Plus the little tiny forearms make it look like some demented nightmare beast from the fertile mind of Tim Burton. A+

Velociraptor
These guys got a lot of press from "Jurassic Park," but let's face it, they're pretty lacking. They couldn't even manage to eat two little kids, one of whom had only minutes before been turned into a toaster pastry. Sure, they got the hunter, but he was coming up with cute last words when he should have been running like a bunny. And then all three of them got totally worked by a baby Tyrannosaurus! Lame! D!

Stegosaurus
Two words: spiked tail. "Oh, so you're sneaking up behind me to eat my delicious body? WHAM! Spikes! For you! In your head!" Plus it had I-am-an-industrial-monster plates on its back, which while probably for conserving body heat or attracting mates, were impressive-looking. A

Part 2