Machairodus giganteus, saber-toothed cat Tyrannosaurus Rex Others are less easy to

Others are less easy to interpret and may belong to extinct phyla

form the cliffs

Between 1929 and 1937

based on a single lower jaw full of closely packed teeth which he gave the species name Ctenochasma roemeri

296 Index Trilobites of North America are illustrated on this poster

Machairodus giganteus, saber-toothed cat Tyrannosaurus Rex Others are less easy toMachairodus is a genus of large machairodontine saber toothed cats that lived in Africa, China, Eurasia and North America during the late Miocene 4. 5 to 5 million years ago. It is the animal from which the subfamily Machairodontinae gets its name and has since become a wastebasket taxon over the years as many genera of saber tooth cat have been and are still occasionally lumped into it. In general Machairodus was similar in size to a modern lion or