CAM BRIAN SYSTEM

term to the earliest fo iliferous system Overlying the Archean or Cam brian system, the oldest Geological Record, and overlaid Silurian system. It derives its from Cambria (i.e. Wales), where specially well developed, attaining places a thickne of 12,000 ft. also occur in Shropshire, War wicks hire, Ireland, and north-western It is met throughout Europe at from Scand in a via to Bohemia, occupies vast areas of eastern America. The Cam brian rocks zites, and conglomerates, with Bale of shales and slates. In i me stones are prevalent, and in with ma es of volcanic rocks. ' Fo ils are numerous and, the earliest discovered forms of they show an advanced development pointing to still lower, lost, or covered ancestors. ‘The most teristic fo ils are the Trilobites lus, and the Brachiopod Lingula from the Port Madoc slates. only discovered plants are regarded Algee (Eophyton). The system Britain is subdivided as follows:— Tremadoc slates Upper eae flags (Olenus