18 



ppo 316-318), Of these, 45 were various kinds of poly- 

 chaetes, 20 were mollusks, and 3 were echinoderraSo 

 Allowing for changes in systematic nomenclature, about 

 half of the polychaete species are the same as those in 

 Santa Monica Bay, and the other half may be kinds limited 

 to more northern or colder waters. The ratio of poly- 

 chaete numbers to total individuals counted, in various 

 depths was given as follows: 5016:5276; 36:266(a clam 

 bottom); 6:104 (a clam bottom); 2058:2683; 84:205 (a 

 snail bottom); 1659:1993; 1294:1368; 45:1454 (a holothurian 

 bottom); 35:562 (a holothurian bottom); and 39:132 (an 

 echinoderm bottom). From this analysis it will be seen 

 that mollusks are limited to shallower, echinoderras to 

 deeper bottoms, and polychaetes are prominent in all 

 depths. Smaller crustaceans, which might have been present, 

 were not noted, Ophiuroids were said to be most abundant 

 in 90 feeto 



Benthonic studies in Japan in the northwestern 

 Pacific (Miyadi and associates, 1940) in shallow (less 

 than 60 feet) nonpolluted areas, emphasized the prepon- 

 derance of certain groups of animals, Polychaetes and 

 mollusks constituted the major parts, with echinoderms 

 and smaller crustaceans next in numbers and all other 

 kinds less than 3%, Two kinds of communities were reco- 

 gnized, a Maldane (bambooworm) in the deeper muddy or 

 sandy bottoms, and a Cerithium (snail) in shallower 

 shelly bottoms. The Maldane was commonly associated 



