2 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 27 



Following the shelf studies, the investigations were concerned 

 with thirteen deep, submarine basins off southern California. One 

 hundred seventy-two large Campbell grab samples were taken in depths 

 of 627 to 2571 meters. Their analyses resulted in the documentation 

 (Hartman and Barnard, 1958-60) of 317 species of metazoan animals. 

 They belonged chiefly to four major groups of animals with the follow- 

 ing distribution: 170 kinds of polychaetes ; 55 crustaceans of which 34 

 were amphipods, 10 isopods, 3 tanaids, 2 cumaceans, 2 ghost shrimps, 



I munnid crab and 3 or more ostracods ; 30 echinoderms of which 22 

 were ophiuroids; 35 mollusks of which 17 were pelecypods, the other 

 18 including gastropods, scaphopods and solenogasters ; 27 other 

 species including coelenterates, echiuroids, sipunculids, enteropneusts 

 and ascidians. Highest specific values were found in the Catalina and 

 San Pedro basins, with 119 and 115 specimens to a square meter 

 respectively, and lowest values were in Santa Monica, a longshore 

 basin, and San Nicolas and West Cortez basins, each with 12 speci- 

 mens to a square meter. Standing crop values were uniformly low, 

 ranging from about 50 grams to a square meter (in a sample from an 

 outer basin, containing a large echiuroid) to a low of 1.5 grams to a 

 square meter in San Clemente basin. The number of specimens varied 

 from a high of 123 to a square meter in Catalina basin, to a low of 



I I in Santa Monica basin. 



The continuation of the benthic program resulted in the recovery 

 of many species unknown to science. Some have been described (Hart- 

 man, 1961, and Barnard, 1959-1962), but many others, especially 

 from the lower ends of canyons, remain to be done and are currently 

 under study. 



The third aspect of the benthic program was the investigation 

 of the submarine canyons, of which 13 were sampled and the biological 

 results given below. This sequence of studies — shelf, basin, canyon — 

 from a single geographic area, the borderlands of southern California, 

 makes possible a comparison of quantitative biological evaluations. 

 It should be noted, however, that slope depths are still largely unex- 

 plored, and future studies might concern themselves with sampling 

 these areas, starting at about the 200 meter depth to threshold depths 

 of all the basins. 



The procedures for taking and processing the samples have varied 

 little except for the substitution of a larger, Campbell grab in deeper 

 bottoms, instead of the smaller orange-peel-grab used in the first 



