Historical Review. Earliest Literature.—The earliest published opinion concerning the age of the beds now known as the Chico formation seems to be that of Dr J. B. Trask,* who described Ammonites chicoensis and Baculites chicoensis in 1856. On account of the modern aspect of the fossils associated with those species he referred the strata containing them to the upper Eocene. Shortly afterward Professor J. S. Newberry† discussed the same beds and, while admitting the presence of modern types of mollusks, considered that the cephalopods were stronger evidence of their Cretaceous age. He also stated that he had obtained a collection of fossils from Nanaimo, Vancouver island, that proved the Cretaceous age of the coal beds at that place. These fossils were placed in the hands of Professor F. B. Meek,* who soon afterward described them. Although at that time he thought that the entire collection came from Nanaimo, he . . .
- © 1892 Geological Society of America