In conjunction with the program of bottom sediment investigation in progress at the Woods Hole Oceanographic Institution, a series of samples of sand from the outer beach of Cape Cod, Massachusetts, were subjected to mechanical analysis. Study of the results of some 234 analyses indicates that the finest grained sand is within the cliff or source section. Both to the north and to the south in the wave-built sections the median diameters increase. The increase in the direction of drift was checked by a repetition of sampling in the cliff and northern wave-built sections the following summer. With the aid of evidence from near shore bottom samples, the unusual condition is shown to result from loss of finer grades in the material supplied by cliff cutting as longshore drift takes the material to leeward.