. Bulletin of the Geological Society of America. Geology. CURRENT CUSPATE FORELANDS. 407 what the form there shown tells us of the history of their formation. These charts cover such a large area and are executed in such detail that it is impossible to reproduce them satisfactorily for the purposes of this paper. The Coast Survey charts are accessible to many, and the facts which are here from them will be much better apprehended with the charts in hand. In figure 4 is given atypical drawing of a current cuspate foreland. In it are combined those features of the three Carolina capes and
. Bulletin of the Geological Society of America. Geology. CURRENT CUSPATE FORELANDS. 407 what the form there shown tells us of the history of their formation. These charts cover such a large area and are executed in such detail that it is impossible to reproduce them satisfactorily for the purposes of this paper. The Coast Survey charts are accessible to many, and the facts which are here from them will be much better apprehended with the charts in hand. In figure 4 is given atypical drawing of a current cuspate foreland. In it are combined those features of the three Carolina capes and cape Canaveral which the author deems impor- tant to show the method of growth. Former positions of the shorelines are indicated by the ridges of dunes built by the wind along the shore. Such former positions are beau- tifully indicated in Canaveral (C. S., 160, 161), where three or four successive posi- tions of the outline of the cusp, each further to the left than the preceding, are delineated, besides many lines of aggradation in each position. Similar lines of growth are seen at cape Fear where the present right shore- line cuts off the eastern ends of the four dune ridges extending east-southeast from the light-house and curving sympathetic- ally with the left shoreline. Cape San Bias, on the west coast of Florida (C. S., 183,184), shows four stages on the right side and nine successive stages of aggradation on the left side. A more striking example of aggrada- tion lines is seen in the cusp of Darsser cape in the Baltic (Germ., 61,62, 63), where thirty-eight systematic and successive shore- lines are indicated by dune ridges. The three criteria of form, offset, overlap, and stream deflection, by which we may recognize the direction of dominant movement along- shore are all seen along the Carolina coast, and are shown in the type drawing (figure 4). To make the point clearer each of the criteria will be considered separately and occurrences pointed out. The typical hooke
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