15 



Among the glycerids, Glycera americana is predominantly 

 present in mixed bottoms in shallow water o It gives way 

 to Go capitata in finer sediments and deeper water; to 

 G. tesselata at moderate depths, and to G, branchiopoda 

 at deepest levels. Other kinds of systematically-related 

 animals have shown similar patterns of replacement with 

 differences in depth and kinds of sediments. In Santa 

 Monica Bay, such species are in the spionid, magelonid, 

 cirratulid, paraonid, nephtyid, goniadid, and other family 

 groups o 



The enteropneusts (acorn worms) are noteworthy for 

 their occurrence in shallow to deep areas. Members of 

 the Spengellidae are represented by no less than three 

 species, and the Ptychoderidae by one or more« Saccoglossus 

 of the spengellids occurs in shallow soft bottoms, and 

 Schizocardium (with perhaps more than one species) has 

 been found in depths of a few feet (in Zone II) to about 

 2300 feet on the Palos Verdes slope^ Stereobalanus has 

 a similar wide vertical range, and the ptychoderids have 

 been found in shallow area (Woodwick, in Hartman, 1955). 



Faunal Affinities 



Geographical 



Santa Monica Bay belongs to the temperate east 

 Pacific faunal subdivision, or the Californian Province 

 (Ekman, 1953, pp<, 151-156), which reaches north to about 

 42 north latitude (near Cape Mendocino, California). At 



