+---+--------------------------+--------------------------------------- | |_Epochs and Formations._ |_Faunal Characters._ |C | | |a |--------------------------+--------------------------------------- |i |POST-PLIOCENE. |Man. Mammalia principally of living |n | Glacial Period. | species. Mollusca exclusively recent. |o | +--------------------------------------- |z |PLIOCENE, 3,000 feet. |Mammalia principally of recent genera |o | | --living species rare. Mollusca very |i | | modern. |c | +--------------------------------------- | |MIOCENE, 4,000 ft. |Mammalia principally of living |o | | families; extinct genera numerous; |r | | species all extinct. Mollusca largely | |OLIGOCENE, 8,000 ft. | of recent species. |T | +--------------------------------------- |e |EOCENE, 10,000 ft. |Mammalia with numerous extinct families |r | | and orders; all the species and |i | | most of the genera extinct. Modern |a | | type Shell-Fish. |r | | |y | | +---|--------------------------+--------------------------------------- | |LARAMIE, 4,000 ft. |Passage beds. | |--------------------------+--------------------------------------- |M |CRETACEOUS, 12,000 ft. |Dinosaurian (bird-like) Reptiles; |e | Chalk. | Pterodactyls (flying Reptiles); |s | | toothed Birds; earliest Snake; bony |o | | Fishes; Crocodiles; Turtles; |z | | Ammonites. |o | +--------------------------------------- |i |JURASSIC, 6,000 ft. |Earliest Birds; giant Reptiles |c | Oolite. | (Ichthyosaurs, Dinosaurs, | | Lias. | Pterodactyls); Ammonites; Clam- and |o | | Snail-Shells very abundant; decline |r | | of Brachiopods; Butterfly. | | +--------------------------------------- |S |TRIAS, 5,000 ft. |First Mammalian (Marsupial); 2-gilled |e | New Red Sandstone. | Cephalopods (Cuttle-Fishes, |c | | Belemnites); reptilian Foot-Prints. |o | | |n | | |d | | |a | | |r | | |y | | |---|--------------------------+--------------------------------------- |P |PERMIAN, 5,000 ft. |Earliest true Reptiles. |a | +---------------------------------------