30 INTRODUCTION 



region in the eastern states. There has been some difference of 

 opinion as to whether this treeless area should be called a prairie 

 or not, but at any rate the natural condition of the tract seems to 

 be without shrubs or trees, except along the few water courses, both 

 glacial and modern, that are found there. It has been suggested 

 that the peculiar soil conditions are to be accounted for by an 

 ice-jam, just to the north of the area in glacial times, which at the 

 recession of the ice debouched a great amount of sand and gravel 

 over what is now the Hempstead Plains. There seems to be some 

 evidence of a congestion of morainic material towards the north, 

 through which, owing to the great pressure of water and ice to the 

 northward, a glacial stream, loaded with sand and gravel, is as- 

 sumed to have forced its way. That such an assumption may be 

 gratuitous in no way disposes of the very remarkable soil condition 

 now found on this area, supporting as it does a flora that is char- 

 acteristic. As in the case of the limestone regions in the north, 

 it is doubtful if there are any endemic plants on the plains. But 

 that there are many plants on this treeless area that are rare or 

 perhaps wanting on other parts of our coastal plain is the fact. 

 Some of these include the following, which are more common on 

 or near the plains than in the surrounding region: 



Panicum lucidum, Cathartolinum medium, 



Panicum aculeatum, Kneiffia riparia (?), 



Fimbristylis puberula, D as y Stephana Saponaria, 



Rubus flagellaris, Agalinis decemloba* 

 Lespedeza angustifolia, 



There are many others and future exploration of this very interest- 

 ing region will doubtless bring to light more information in regard 

 to the origin of this peculiarly local prairie-condition. f 



49. A peculiar condition has been noted in Connecticut by 

 Dr. Nichols,| in regard to some coastal plain species. He has 

 recorded among others the occurrence of the following in or near 

 coastal Connecticut that are unknown on Long Island. They 

 are all coastal plain species found southward, but not recorded 

 from Long Island: Meibomia sessilifolia, Myriophyllum pinnatum, 



v * Apparently its only station in our range. 

 ^ t Harper, R. M. The Hempstead Plains of Long Island. Torreya 12: 277-287. 

 1912. 



X Nichols, G. E. The vegetation of Connecticut. Torreya 13: 89-112. 1913. 



