During the past eighty years the Hawaiian Islands have been visited by various geologists, few of whom saw all the islands of the group or remained on the islands for any considerable length of time. Certain of the tectonic features of the islands have received only scant attention, while others have never been examined. It is the purpose of this paper to call attention to those features which have not been described as well as to offer suggestions concerning those previously noted. Various theories which have been proposed to account for the alignment of the volcanoes, both active and extinct, and for their age relations, are reviewed in the light of a recent reconnaissance on every island of the group.
A notable alignment and spacing of the volcanoes in the island groups of the Pacific was noted at an early date by Dana in the Hawaiian Islands . . .