Volcanic Rocks of the Upper Miocene Period. — Madeira. — Grand Canary.
— Azores. — Lower Miocene Volcanic Rocks. — Isle of Mull. — Staffa and
Antrim. — The Eifel. — Upper and Lower Miocene Volcanic Rocks of
Auvergne. — Hill of Gergovia. — Eocene Volcanic Rocks of Monte Bolca. —
Trap of Cretaceous Period. — Oolitic Period. — Triassic Period. —
Permian Period. — Carboniferous Period. — Erect Trees buried in
Volcanic Ash in the Island of Arran. — Old Red Sandstone Period. —
Silurian Period. — Cambrian Period. — Laurentian Volcanic Rocks.