Death of the Dinosaurs

The dinosaurs died before the Flood, never making it onto the Noah's Ark.  The Bible says that the animals came onto the Ark by twos, the male and his female.  One thing it never mentions is dinosaurs.  Something like this would get special attention.  Why else were there no T-Rexes mentioned getting on the Ark?  They would only have been able to fit on the first floor, and then they would have busted through the second floor, and maybe the third.