COMPLETE HARTMAN: POLYCHAETES FROM CALIFORNIA 111 



acicular spines are distally falcate and slightly curved in their distal 

 half. 



Chaetozone multioculata differs from other species of the genus in 

 having transverse rows of eyes on the prostomium ; the body consists of 

 fewer segments and the buccal region is prolonged. 



It is associated with an echiuroid, Listriolobus pelodes Fisher, and 

 many (32 species) other polychaetes including Hesperono'e laevis (see 

 above), Ceratocephala crosslandi americana Hartman and Marphysa 

 disjuncta (see above). It was taken only from the Ventura shelf, Cali- 

 fornia, in 20}/2 fms, from green mud sediments. 



Chaetozone gracilis (Moore) 1923 



Caulleriella gracilis Berkeley and Berkeley, 1952a, p. 37. 

 Hartman, 1959b, p. 401. 



Collections. Many stations of the VELERO IV, from southern 

 California, in shelf and slope depths. 



Length of mature individuals is 30 mm or less ; width about 1 mm ; 

 segments number about 110. The body is slender, barrel-shaped between 

 segments 10 to 40, then slenderer, and tapers thereafter. Anterior seg- 

 ments are most crowded, and in middle through posterior segments they 

 are longer, and three to three and a half times as wide as long. The 

 prostomium is acutely pointed in front and lacks eyespots. Palpi, on 

 the first setigerous segment, are inserted above and in front of the first 

 notopodia ; they are longitudinally grooved and usually coiled. 



Lateral branchiae are inserted immediately above and slightly behind 

 the notopodial mound ; they usually occur on most segments but some- 

 times the first one and last 20 segments lack them. Notopodial setae 

 are slender and capillary through most of the body; a far posterior 

 region may have 2 or 3 thicker, acicular spines in a ramus, accompanied 

 by capillary setae. Neuropodia have transverse series of 7 to 12 dark, 

 thicker, shorter setae alternating with blunt, acicular spines, present 

 from segment 35 to 40, and continued back to the posterior end. These 

 spines are unique in that the distal end is delicately serrated, with 3 

 distal striations resembling compressed teeth, and the shaft tends to 

 be fuscus. 



The body terminates posteriorly in a small, triangular lobe behind 

 the anal aperture. Some specimens are encased in spirally twisted thin 

 tubes (Sta. 4820) not much thicker than the diameter of the occupant, 

 suggesting that a tube may be constructed at maturity. 



