Era
Cretaceous
216
Tertiary
100
Jurassic
72
Ordovician
72
Paleozoic
65
Devonian
64
Miocene
63
Eocene
59
Carboniferous
51
Mesozoic
51
Pleistocene
51
Pliocene
47
Cenozoic
44
Permian
43
Cambrian
38
Mississippian
37
Pennsylvanian
35
Quaternary
34
Oligocene
33
Triassic
33
Silurian
31
Holocene
20
Neogene
17
Paleocene
12
Precambrian
10
Paleogene
8
19th century
3
20th century
3
Proterozoic
3
1818-1891
2
Archaean
2
Phanerozoic
2
1790-1852
1
1799-1847
1
1804-1892
1
1810 or 1811-1889
1
1835-1919
1
1843-1901
1
18th century
1
Dovanian
1