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plants inhabiting them, but except in a general way the subject 

 of plant societies was not considered. These sand plains are a 

 conspicuous feature of the central lowland of Connecticut. From 

 a physiographic standpoint they represent outwash plains, de- 

 veloped during the final retreat of the continentab glaciers, and 

 now considerably dissected by stream erosion. One series of 

 these plains stretches northward from New Haven, along the 



Fig. 5. Vegetation ofsand plains in late summer, North Haven. The plant 

 so common on the sand here] is- the annual, Trichostema dichotoma. Note the 

 greater abundance of this plant in the wagon ruts — perhaps due to more favorable 

 moisture relations there. _ In the right foreground are Andropogon scoparius and 

 Asclepias syriaca. 



east side of the Quinnipiac River, for about sixteen miles. The 

 soil varies in texture from sand of medium fineness to coarse 

 gravel. Moisture is more or less abundant throughout the year 

 at a short distance below the surface, but, except in moist weather, 

 the superficial soil layers are dry. This latter fact, coupled with 

 wind sweep, the burning heat of the sun on the sand, and the high 

 rate of evaporation, hinders the establishment of vegetation. 

 The greatest divergence in plant succession on such an area 



