usually in September or June, and during the last several years, these 

 peaks have been very consistent (Fig. 13 J). At JC, densities of Tharyx 

 spp, in 1983 were consistent with previous years values; those at GN were 

 slightly higher, continuing a trend of increased density which began in 

 September 1978 period. 



Chaetozone spp. 



Chaetozone spp. are surface deposit-feeders that commonly inhabit the 

 muddy interstices within mussel beds and among kelp holdfasts. Chaetozone 

 spp. were among the top four at only GN in 1983, but were also among the 

 top ten at EF and JC in 1983. This taxon has been a consistently dominant 

 organism at GN (Fig. 13 K) , while at the other stations, it has exhibited 

 large year-to-year changes in abundance. For example, it was very abundant 

 at EF from September 1979 to September 1980, although prior to and after 

 this time, densities were relatively low. Chaetozone spp. are frequently 

 found in highest densities in September, although like many other subtidal 

 taxa, it has been collected in high densities at other times of the year. 

 Overall, the 1983 abundance of Chaetozone spp. at all stations was similar 

 to those of 1982, but remained well below values obtained from September 

 1979-80. 



Exogone hebes 



Exogone hebes is a small deposit-feeder common in the silt layers of 

 sandy deposits from coastal to deep-sea areas of New England. During 1983, 

 this species was among the top four at only IN, and among the top ten at 

 EF. Although Exogone has not consistently been among the most abundant 

 forms at IN, the high density in June 1983, resulted in high annual 

 densities (Fig. 13 L) . In 1983, densities of Exogone were highest in June 

 at all stations; this seasonal peak has characteristically occurred over 

 the last six years. Relative to previous years, the 1983 densities of 

 Exogone were higher (IN) or among the higher (EF) values obtained since 

 1976; these at JC and GN in 1983 were within the ranges of previous years. 



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