During the three days which followed, our progress was exasperatingly slow. I doubt if we made ten miles in the entire three days. The country was hideously savage, so that we were forced to spend hours at a time in hiding from one or another of the great beasts which menaced us continually. There were fewer reptiles; but the quantity of carnivora seemed to have increased, and the reptiles that we did see were perfectly gigantic. I shall never forget one enormous specimen which we came upon browsing upon water-reeds at the edge of the great sea.
- Edgar Rice Burroughs, Chapter 3, "The People That Time Forgot" (1918)
Most of the biota of Caspak are terrible creatures indeed, locked as they are in what seems like a constant battle for survival: they menace the crew of U-33, they pursue the hominids of the island, they feast upon each other and fight to the death.
Diplodocus ajori ("Ajor's Double-Beam") is different: even among the beasts of Caprona, this animal is unique.