NO. I FORAMINIFERA IN LONG ISLAND SOUND BUZAS 21 



Size of the Living Population 



The actual number of living individuals per station for each of the 

 abundant species was averaged for the depth ranges 0-10 m., 10- 

 20 m., 20-30 m., and 30-40 m. The results are shown in figure 8. 

 Elphidium clavatum averages over 300 living individuals at depths 

 of less than 10 m. and over 100 at depths of 10-20 m. It averages 

 less than 20 individuals at depths greater than 20 m. Buccella 

 frigida shows a maximum in the range 10-40 m., whereas Eggerella 

 advena is most abundant at depths of greater than 20 m. Figures 

 5-7 show that E. clavatum is relatively abundant at depths of less 

 than about 20 m. and that E. advena is relatively abundant at greater 

 depths. The histograms of figure 8, however, show that in terms of 

 numbers of living individuals E. clavatum is by far the most abundant 

 species, and therefore the greatest concentration of living individuals 

 is in the near-shore areas. 



Figure 9 shows the distribution of the living population in numbers 

 of individuals per uniform sample. The numbers used for traverse 3 

 are averages from the seasonal stations. At depths of less than 15 m. 

 the living population is usually over 200 individuals. The larger part 

 of the central areas is in the range of 30-90 individuals per sample. 

 At stations 8-11 in traverse 3 and stations 44 and 45 in traverse 4 the 

 number of living individuals is in the range of 90-200. Occurrences 

 of less than 30 individuals are most common along the north shore of 

 Long Island east of longitude 73° and in traverse 5. 



The standing crop of Foraminifera in L.I.S. is estimated to be 110 

 per sample. This figure was obtained by averaging the number of 

 living Foraminifera in the top centimeter of the 88 seasonal samples 

 of traverse 3. Because this average is based on many stations sampled 

 seasonally, it is believed to be the best estimate attainable. At depths 

 of 10-20 m. the average number of living Foraminifera in the seasonal 

 stations of traverse 3 is 177, while at depths of greater than 20 m. it 

 is 62. The shallowest station in the seasonal traverse is 10 m., and 

 therefore to obtain an estimate of the living population in the 0-1 0-m. 

 range, miscellaneous shallow-water stations were used. The area 

 just north of Long Island east of longitude 73° was excluded. The 

 average number of living Foraminifera at eight stations in the 0-10- 

 m. range is 335. 



ZONATION OF THE LIVING POPULATION 



Examination of the data indicates that the three most abundant 

 species can be used to construct a foraminiferal zonation of L.I.S. 



