Lower Cambrian fossils were first discovered by Emmons in eastern New York almost a century ago. Since then, many specimens have been obtained from the Appalachian region, but the stratigraphy received little attention. Recently, interest in the study of the early Paleozoic rocks of the Appalachians has revived.
A. F. Foerste described the cystids. Consequently, the new genus Lepidocystis and the species L. wanneri are to be attributed to him.
In this paper the name Appalachians applies to a region characterized by a particular stratigraphic history and geologic structure and, therefore, is not used in a physiographic sense. The region embraces the Appalachian Mountains from Alabama to eastern Pennsylvania, or the area to which the physiographic term usually applies. Inasmuch as similar stratigraphic conditions and geologic structure continue beyond Pennsylvania, the term Appalachians must also embrace the Hudson and Champlain valleys, and the St. Lawrence Valley to . . .