8 



The broad flat shelf extending west from Hyperion 

 to the upper end of Santa Monica Canyon (Zone I) comprises 

 85 to 90 square miles. It can be divided into faunal 

 areas expressed in terms of distance from the outfall. 

 Six faunal groups are named, each with west (I W), south- 

 west (I SW) , and northwest (I NW) sectors. The boundaries 

 as noted in the report of May 7, 1956 are retained except 

 that the outer fringe of the Limited-Enriched-Fauna in 

 I W has been moved west about a fifth of a mile to encompass 

 all of the stations in the I W-12 sector (Figure 2). This 

 fauna, as well as the adjacent Unliraited-Diminished- 

 Fauna, have been more completely sampled since the last 

 report was issued. 



Methods and Equipment 



The samples taken with the Hayward orange peel grab 

 were screened on board ship through sieves of which the 

 finest measured 24 meshes to the inch, bottled in suitable 

 containers, and fixed with formalin added to seawater. 

 As soon as possible thereafter the samples were trans- 

 ported to the laboratory where cleaning and analyses 

 were done (Hartman, 1955). Because of these collecting 

 methods, many smaller metazoan animals (especially smaller 

 crustaceans, worms, raollusks and others) were undoubtedly 

 losto However, the counts of animals were high in spite 

 of such unmeasurable losses and the species are believed 

 to be characteristic of the areas investigated. 



