^ % cj^ % c^ % <?;. ^ ^ ^ ^ ^ '^c -^c ^o^ t^^ '^c t-^ 



Figure 7. Dendrogram resulting from classification of annual infaunal collections at Millstone intertidal stations from 

 September 1979 - June 1985. 



The first major group of station/years (Group I) included all WP and GN collections and was father 

 subdivided into two subgroups, (jroup A contained CjN years, and the 1985 WP collection; similarity 

 among these station/years and their separation from other collections was due to shared high numbers 

 of oligochaetcs and 1 1 aplnscoloplos fragilis. Subgroup B (remaining WP years) separated from other 

 years because of very high densities of rhynchocoels, Streptnsyllis arenae and Paraonis fulgens. 



The .ICr collections (Group II) had relatively low similarity with GN and WP because of the high 

 numbers of oligochaetcs, Scolecnlepides viridis, Hediste diversicolor and Polydora ligni found at JG. The 

 relatively high similarity among most .IC years reflected temporal constancy in the species composition 

 at this station and the level of similarity among years was dependent on variations in the abundance of 

 taxa rather than shifts in composition. For example, the subgroup containing 1981, 1982, 1983 and 

 1985 coUccticins included very high numbers of oligochaetcs, and high numbers of Polydora ligni, Capitella 

 spp. and Gammaf-us lawrencianus. Collections from other years, had similar species composition, but 

 densities of these species were considerably lower. 



24 



