Page:A Treatise on Geology, volume 1.djvu/172

 156 been found abundantly in many parts of Scotland, and rarely in Herefordshire and Breconshire.

We now pass the Severn, and find a great change. North Devon exhibits both the old red series and the true carboniferous series in an aspect much different from their northern types. The series stands thus:—

We may now proceed to South Devon. The groups here observed are not to be placed in strict mineral or structural affinity with the coeval series in the north. The best section is afforded in Plymouth Sound, but enormous contortions prevail.

By tracing these beds farther westward Silurian strata appear beneath them.

Organic Remains.—By uniting in one summary