ENDEMISM IN THE NORTH PACIFIC OCEAN, WITH 



EMPHASIS ON THE DISTRIBUTION OF MARINE 



ANNELIDS, AND DESCRIPTIONS OF NEW 



OR LITTLE KNOWN SPECIES 



By 



Olga Hartman 

 Allan Hancock Foundation 



Recent studies in the soft ocean bottoms of the San Pedro Basin, 

 California, in depths of 4 to 495 fathoms, have disclosed the presence of 

 an unknown, greatly diversified metazoan invertebrate fauna. Its geo- 

 graphic extent to north or south of the region studied is not yet known, 

 but the horizontal limits of its components have been established within 

 the area studied (Hartman, 1955). 



Through extensive studies over many years, it has been established 

 for European seas that the animals living within the bottom, or the 

 Infauna, are very nearly the same in all areas, from Arctic to tropical 

 seas (Thorson, 1951, pp. 481-489). Distinct communities of greater 

 or lesser extent have been named, and the presence of dominants and 

 recessives has been noted so that the composition of a given area is 

 predictable within limits. 



Current studies on the Infauna of ocean bottoms of southern Cali- 

 fornian waters have shown that the bottom-dwelling animals differ from 

 those of other parts of the world not only in the presence of many species 

 or genera not known elsewhere, but also in the absence of some known 



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