The time has not yet arrived for the construction of a determined geological cross-section of southern New England from the Hudson River on the west to the sea on the east coast of Massachusetts. Partial sections have been published for the western part of Massachusetts, including the Triassic area of the Connecticut Valley; detailed local sections have been made by Perry about Worcester, Massachusetts, and detached sections have been put forth to illustrate the structure of the Boston and Narragansett areas, in eastern Massachusetts. Pumpelly, Wolff, and Dale have given a section of Greylock Mountain.
Professor Emerson, in his latest map of Massachusetts, refrained from publishing a cross-section of the State, probably because of the difficulty of doing so in the region of schists occupying the middle area between Worcester and the Connecticut boundary. Here the question of the geological age of the schists regarded by Emerson as mainly . . .