CHARACTERISTICS 



605 



The following description of beach cusps is based largely on m}^ own 

 observations^ but is corroborated by the accounts furnished by others : 



FORM 



When most perfectly developed, the ideal beach cusp has a shape sug- 

 gesting an isosceles triangle, and is so placed that the unequal side (here- 

 after called the base) is parallel to, but farthest from, the shoreline. 

 The "triangle'^ may be short and blunt, or may be so greatly elongated 

 that the two equal sides extend far down the beach and finally unite to 

 form an acute point (hereafter called the apex) . These same sides may 







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Figure 3. — Variations in the Form of Beach Cusps 



be relatively straight, but are more often concave, sometimes convex, out- 

 ward. The actual variations in form are numerous and wdde (figure 3). 

 Every gradation can be found from well developed triangular accumula- 

 tions of sand or gravel to widely spaced heaps of cobblestones of no defi- 

 nite shape. The cusps may constitute the serrate seaward side of a 

 prominent beach ridge, or may occur as isolated gravel hillocks separated 

 by fairly uniform spaces of smooth sandy beach. They may be sharply 

 differentiated from the rest of the beach, or may occur as gentle undula- 

 tions of the same material as the beach proper, and so be scarcely dis- 

 cernible as independent features. Indeed, the variations in beach cusps 



