38 



time that they cause production of definitive populations in 

 spite of local dissimilarities of other features which are 

 recognizable but not detrimental. Two populations, inshore 

 and offshore, may have drifted into separate localities from 

 a region of common origin so recently that they appear to 

 retain the earlier likenesses in recognizable form, although 

 already acquiring important differences. A population may 

 develop in an offshore area and expand into nearshore waters, 

 adapting itself to environmental features of the new area as 

 the expansion progresses. Thus, the constant movements of 

 the plants in one direction or another add enormously to the 

 difficulty of conducting researches and of understanding the 

 results. 



Considering all of these conditions, the wonder may be 

 not the inconsistencies of plankton near the three outfalls 

 during the past year, but rather the constancy of their 

 occurrence. 



Distribution with Distance from the Outfall . The noted 

 distribution of plankton with distance from the three outfalls 

 apparently corresponds to the increased nutrients in the dis- 

 charge area. In Figure 13, the average volume of plankton in 

 the winter has been plotted against distance from the boils, 

 and in Figure 14, the average numbers in June and July at 

 Orange County. Each shows a remarkable increase within 1,000 

 feet of the boil, an increase which is greatest at Whites Point, 

 The average volume at distances greater than 5,000 feet was 

 1.1 ml per net haul when the data for these curves were 

 gathered. This was double the amount in the waters prior to 



