656 PROCEEDINGS OF THE ACADEMY OF [Oct. , 



the sea sweep Ihe particles up the slope until they arrive at the 

 crest wall, where they are caught in the tangle of beach grasses 

 and other plants, and are protected from the currents of air. 

 When the movement of sand is most rapid, it may bury these 

 plants out of sight, but most of them are tolerant of this covering 

 of sand, and quickly grow upward and make a new entanglement 

 for the moving sand. Such plants are ^mmo/)/u7a arenana (L. ) 

 Link, Prunus maritima Wang, and others previously described. 

 In this manner, the crest of the beach grows upward and the lee 

 slope of Ihe sand hill is always the steepest one. The dunes of 

 the New Jersey coast are not so marked as some in other parts of 

 the world (as, for example, at Eccles, in England, where one of 

 these dunes in the last century invaded the village and buried the 

 dwellings and the parish church so that even the top of the spire 

 was hidden) for the reason that the prevailing winds of New 

 Jersey are from the west ; and the sand swept up from the sea- 

 margin by the ocean storms and easterly breezes is, to a great 

 extent, carried back by the off-shore winds. Even these dunes 

 would have a precarious existence were it not for the fact that the 

 vegetation, generally quite mxuriant, holds the sand in place. The 

 prevalent west winds and the absence of protecting trees account 

 for the character of tue dimes at Sea Side Park, where the frontal 

 dune slopes gradually up from the windward or landward side to 

 the crest of the dime, the leeward or ocean side being quite steep 

 and declivitous. 



At Piermont, on the contrary, the western or windvvard slope of 

 the dune is the steepest. Here a forest, formerly five hundred feet 

 wider, is being engulfed by the drifting sand. The sand, carried 

 by eddies of the prevailing western winds, but more especially by 

 the winds of ocean storms, ascends the surface of the dune and 

 falls over its crest into the forest. When a stiff breeze is blowing, 

 the sand skims along like drifting snow sufficienily strong to decor- 

 ticate trees. The forest, choked with undergrowth composed of 

 climbing plants and shrubs, as previously mentioned, prevents the 

 access of the western breezes that are prevalent and which are 

 inimical to dune upbuilding, and the sand, therefore, moves relent- 

 lessly carried by the eastern winds that now and then blow upon 

 the forest that engendered the dune. The presence of this forest, 

 therefore, explains the peculiarities of the dune formation at Pier- 

 mont, a£ contrasted Avilh that at Sea Side Park. 



