esented locally by
various kinds and different thicknesses of sediment.[142]

TABULAR VIEW OF THE SUCCESSION OF GEOLOGICAL FORMATIONS AND
ORGANIC REMAINS.

====================================================================
PERIODS. | SYSTEMS OF | CLASSES OF ANIMALS. | PLANTS.
| FORMATIONS. | |
--------------------------------------------------------------------
I. |Ancient Metamorphic |Eozoon and probably other|Graphite and
EOZOIC |rocks of | Protozoa. |Iron Ores
PERIOD. |Scandinavia, | |representing
|Canada, etc. | |Vegetable
| | |Matter.
--------------------------------------------------------------------
II. |Cambrian. |_Radiata_--Hydrozoa, |Algae.
PRIMARY | | Echinodermata |
OR | | (Cystideans). |
PALAEOZOIC| |_Mollusca_--Brachiopoda, |
PERIOD. | | Lamellibranchiata, |
| | Gasteropoda, Cephalopoda|
| | (Bivalve and Univalve |
| | Shell-fishes). |
| |_Articulata_--Annelida, |
| | Crustacea (Worms and |
| | Soft Shell-fishes of the|
| | lower grades). |
| | |
|Lower Silurian. |_Radiata_--Anthozoa |Algae.
| | (coral animals), |
| | Echinodermata |
| | (sea stars, etc.). |
| |_Mollusca_--Polyzoa, |
| | Tunicata. |
| |Other Mollusks and |
| | Articulates as before. |
| | |
|Upper Silurian. |Radiates, Mollusks, and |Acrogenous
| | Articulates as before. |Land plants.
| |_Vertebrata_--First |
| | Ganoid and Placoid |
|