1889.] NATURAL SCIENCES OF PHILADELPHIA. 135 



extreme tips alone remain above the sand. How many are abso- 

 lutely covered, one can hardly even guess. 



The force at work here is plain enough. The wind from the 

 north and north-east drives the sand to the hill-top, and when it 

 reaches the crest, gravity carries it down the southern declivity. 

 Once the forests have been killed, and the leaves are fallen, there is 

 nothing to arrest the force of the wind and the slow process of 

 uncovering the tree trunks by the sand drifting away from them 

 begins. This, however, appears to be simply shifted further south, 

 covering up fresh forests as it advances. While, therefore, ground is 

 being lost to the forests and to the hay makers in the south and west,, 

 there is a gain on the north, for enough of the sand remains there 

 to raise the general level of these meadows slightly, and to make them 

 less subject to frequent overflow. Indeed as we have seen, a second 

 forest growth is commencing on that very spot. 



To one familiar with the dunes on Cape Cod, those of Lewes are 

 striking from the fact of the absence of the wild rose, blueberries, 

 beach-plums, etc., which one finds so common in the Massachusetts 

 examples. They illustrate further, that we have on our own soil, and 

 within a few hours of this city, the same forces operating which were 

 so .destructive on the shores of the Bay of Biscay. These dunes 

 and trees suggest further that the same remedies which restored a 

 vast area (rescued from the sandy deluge) again to France may in 

 time have to be appealed to here. There is, however, this difference, 

 that whereas, in Europe, it was the Pinus Pinaster Soland. or 

 Maritime Pine that was used to make seaward barrier, we here can 

 safely depend upon the Pinus rigida or Pitch Pine, which is thriving 

 now at Lewes, to accomplish this same result. Indeed from Massa- 

 chusetts south to Lewes, here and there, in sight of the sea and on a 

 most sandy soil this tree is flourishing almost as well as it does on 

 the rocky hillsides in the interior of Pennsylvania. 



May 14. 



Mr. Edw. Goldsmith in the chair. 



Twenty-three persons present. 



A paper entitled " Catalogue of the Muscicapidse in the Collection 



of the Academy," by Witmer Stone was presented for publication. 



Xotes on Corema Conradii. — Mr. J. H. Redfield stated at the 

 meeting of the Botanical Section of the Academy held May 13th, that 

 it had been supposed of late years that Corema Conradii Torr. had 

 disappeared from the pine barrens of New Jersey, the earliest reported 

 station for the plant. He referred to an unsuccessful search for it, 

 made by the late Charles F. Parker and himself in April, 1869, at 

 Cedar Bridge, Ocean Co., N. J., where Dr. Torrey had seen it in 

 1834 and had indicated the exact locality in the Annals of N". Y. Lye. 



