22 



ALLAN HANCOCK PACIFIC EXPEDITIONS 



VOL. 27 



The north wall of Redondo canyon is represented by eight samples 

 coming from depths of 107 to 554 meters. The shallowest contains 

 considerable amounts of gravel and shell fragments mixed with green 

 mud ; one in 113 m has sandy mud. Both are characterized by a high 

 diversity of species belonging chiefly to the outer shelf fauna. Poly- 

 chaetes number 56 species and 524 specimens in the first, and 45 

 species with 609 specimens in the second, of which nearly half were 

 not present in the first sample. A commensal hydroid, Monobrachium 

 parasitum, is frequent on shells of a small clam, Axinopsida, and a 

 small sipunculid, possibly Golfingia sp., (see Fig. 7) in Rhabdamina, 

 an arenaceous foraminiferan, both in shallowest sandy sediments at 

 depths of 107 and 120 meters. Ophiuroids, Amphiodia urtica and 

 A. digitata exist in peak numbers in shallowest parts, together with 



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Fig. 7. ?Golfingia sp., a sipunculid, penetrating Rhabdamina, a 

 foraminiferan, from the upper end of Santa Monica canyon. 

 a. the Rhabdamina partly broken open to show two sipuncu- 

 lids in place, b. a single sipunculid, removed from the host, 

 showing distal end of introvert with oral lobes and sub- 

 terminal spines, and anal pore, x 17. 



