Mark Frangooles, age 30, of Bellevue, Wash., or his question:

When was the Devonian Period?

The Devonian Period is a period in the Paleozoic Era of geological history. It began about 320 million years ago and. ended about 265 million years a‑go. The rocks of the Devonian Period. were first studied in Devon, England, from which the period got its name.

The Devonian 'Period is sometimes called the Age of Fishes. The spas teemed with fish of all kinds and sizes. For the first time in earth s history the dry land was clothed with abundant plant life. There were giant ferns end strange horsetail trees, though flowering plants had not yet appeared.

There were animals, too, on the dry land. Spiders, insects and scorpions left their fossil remains in the Devonian sandstone. ,end. the first amphibians wore trying a now kind of life,, partly on the land and partly in the water.