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ALLAN HANCOCK PACIFIC EXPEDITIONS 



VOL.7 



Because of individual variations noted above, it appears doubtful that 

 these two (S. foliata and S. sacculata) are to be considered distinct; as 

 shovi^n above, the presence of hooks varies vuithin the specified limits. The 

 observed difference in the transverse folds may be at least partly due to 

 differences in age of specimens and methods of fixation. Spionides japoni- 

 cus has been referred to Laonice cirrata (Soderstrom, 1920, p. 220) ; 

 S. foliata by Hartman ( 1936a, p. 32) . The type of Arcidea alata has been 

 examined at the United States National Museum and found to be not a 

 member of the family Paraonidae, but rather a spionid, with palpi broken 

 off near their bases. In all other respects the type specimen agrees perfectly 

 with Laonice cirrata (Sars). 



L. cirrata is cosmopolitan in distribution. 



Genus NERINIDES Mesnil 

 Nerinides acuta (Treadwell) 

 Plate 45, Figs. 1-8 ; Plate 47, Fig. 29 



Spio acuta Treadwell, 1914, pp. 199-201, pi. 11, figs. 14-20. Hartman, 

 1936a, p. 32. 

 Extensive beds of this species have been found in intertidal sandy 

 beaches in southern California, especially along the strand where accumu- 

 lated debris and kelps are swept in, such as the coves at La Jolla, Laguna 

 Beach, etc. It sometimes forms compact beds, or may be present where 

 Thoracophelia rnucronata (Treadwell) is dominant. Its vertical burrows 

 in the sand are recognizable at the surface as minute apertures ; these may 

 be closely packed when abundant. In life the animal is light green, the 

 pigment contained largely in the walls of the alimentary tract and palpi. 



