The previous studies of the Triassic formation of Connecticut, carried on by the senior author of this paper, with the aid of several assistants during various summer vacations for the United States Geological Survey, as well as independently during successive sessions of the Harvard summer school of geology, have been reported upon at different times, as mentioned in a list of papers in a previous number of this Bulletin.† Since then a popular essay, “The Lost Volcanoes of Connecticut,” has been published in the Popular Science Monthly for December, 1891, by the senior author.
All these previous studies have been chiefly concerned with the structure of the formation within its boundaries, which were examined only incidentally until especially studied in recent summers by the junior author. This paper is chiefly concerned with the results thus determined along the eastern boundary of the formation. Our problem is in effect: . . .