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ALLAN HANCOCK PACIFIC EXPEDITIONS 



VOL. 27 



community into Onuphis zones. Capitella often occurs with Pectinaria, 

 but in other samples (see list in Table 6) it occurs in high frequency 

 without Pectinaria. Pectinaria must be examined not so much from the 

 shallow-water end of the spectrum, as from the deeper end. In the 

 shallow-water J mphiodia-community, it forms a major subdominant and 

 one might assume that it has migrated to the canyons from that locus. 

 Because the continental slopes have been poorly studied, it is unknown 

 whether Pectinaria indicates a "normal" community or whether it is an 

 opportunistic dominant of unstable substrate. At first I had expected 



Graph 7. Representative samples of the submarine canyons with 

 paired coefficients of association and their means summarized by 

 blocks. Samples restricted to the Pectinaria and Ileteromastus com- 

 munities with their subassemblages and with comparisons to typical 

 samples of the Maldane and Lysippe zones. 



