ECOLOGICAL PAPERS. 



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during October. (Fig. 2.) The maximum rate never reaches 

 20 cc. per day, the minimum falls below 4cc. while the average 

 for the season is 11.3 cc. daily. 



Following the pines upon the fixed dunes comes Quercus 



Figure 2. Mean daih- evaporation rates in the sand dune plant asso- 

 ciations and in the beech-maple forest. 



velutina, finally forming at a distance of some 600 meters from 

 the last station an almost pure stand of black oak, here referred to 

 as the "oak dune." In the undergrowth are Viburnum acerifo- 



