英文英文字典
英文英文字典
古腾堡计划中的在线英语-英语词典
结果
Trenton period的结果
Trenton period
A subdivision in the lower Silurian system of
America; -- so named from Trenton Falls, in New York. The rocks are
mostly limestones, and the period is divided into the Trenton, Utica,
and Cincinnati epochs. See the Chart of Geology.