Seismic refraction measurements across the New Jersey Coastal Plain, from Bridgeport on Delaware Bay to Avalon on the Atlantic coast, have been made as a continuation of similar measurements of the depth of the crystalline basement made in 1935 at Cape Henry, Virginia, and Woods Hole, Massachusetts, and in 1937 at Barnegat Bay, New Jersey. The standard technique for seismic refraction measurements was followed. Three seismic discontinuities were determined in addition to the one associated with the bottom of the surface gravels covering this part of New Jersey. These discontinuities appear to have the same geologic equivalents as were noted on the Barnegat Bay seismic section. The observed depths are in agreement with the available well data, and the seismic velocity variations noted for the basement discontinuity indicate similar changes in basement lithology as those found along the Barnegat Bay seismic section.