NO. 4 HARTMAN: SPIONIDAE FROM CALIFORNIA 311 



Specimens examined have the following characters. The body is long, 

 attenuate. The prostomium is clearly bifid at its anterior margin ; its car- 

 uncle extends back to the posterior margin of the fourth setiger (hence 

 much longer than in P. caeca Oersted). The first setiger has only a 

 neurosetal fascicle. Branchiae are first present from the eighth setiger, 

 though small; from the ninth they are larger and are continued poste- 

 riorly nearly to the end (in P. caeca they are missing from a long poste- 

 rior end). Hooded hooks are first present from the seventh; they are dis- 

 tally bifid, the angle of the stalk and tip oblique (pi. 48, fig. 42). Stout 

 spines of the fifth setiger are falcate, with an enlargement or boss in the 

 concave region (pi. 48, fig. 41). The pygidium is a flaring disk, entire 

 in its ventral portion, with deep dorsal notch (specimens from San Fran- 

 cisco) or also with shallow lateral notches (specimens from Mugu 

 Lagoon ) . 



P. socialis may be typically an estuarine form. The type locality was 

 given only as "Chile." 



Polydora citrona, new species 

 Plate 45, Figs. 9-16 



The general form is long, attenuate, length 20-30 mm, number of seg- 

 ments 120 or over. It is ochre yellow in life, in striking contrast to the 

 dark sandy mud in which it lives, associated with an anomurid crab 

 (Upogebia). Palpi (presei-ved) extend posteriorly to about segment 8-10. 

 The prostomial ridge is greatly reduced, a minute longitudinal ridge 

 superimposed on the much larger, inflated peristomial, pouchlike ring 

 (pi. 45, fig. 10). Four minute black eyespots, nearly in a straight line, 

 lie just in front of the palpal bases on the ridge. The anterior margin 

 of the prostomium is bluntly rounded, somewhat turned up distally (in 

 lateral view) (pi. 45, fig. 9). A caruncle extends posteriorly to the third 

 setiger but is not conspicuous. 



The first 4 setigers have noto- and neuropodial fascicles increasing in 

 size gradually posteriorly, those of the first the smallest. The postsetal 

 lamellae likewise increase in size proportionately, but nowhere are they 

 larger than those of the postmodified segments. The fifth (modified) 

 segment is large, inflated, fully twice as long as segments proximal to it. 

 It bears a heavy dorsal fascicle of brown spines and a neuropodial fascicle 

 of capillary setae which are nearly as large as those of the next segment, 



