COMPLETE HARTMAN: POLYCHAETES FROM CALIFORNIA 69 



Oxydromus arenicolus glabrus reaches its greatest concentrations in 

 shallow benthos of silt and mixed bottoms and is most frequent near 

 outfalls, where it is associated with Ophiodromus pugettensis (see above). 



Oxydromus brunnea, new species 

 Plate 5, figs. 1-4 



Collections. Velero IV Stations 2393, 2402, 4822, 5102, and some 

 others, all in considerable depths off southern California. 



This is a small, fragile species; length of an ovigerous adult with 

 29 setigerous segments is 7.5 mm with, and 6.5 mm without, everted 

 proboscis. The prostomium and dorsum are conspicuously marked with 

 reddish brown pigment, chiefly as transverse bars across the dorsum 

 (PI. 5, fig. 1). In fresh specimens, the anterior half of the prostomium 

 is dark to within the area of the anterior eyes; a similar pigment forms 

 a dark band across the posterior border of the prostomium, and similar 

 narrow dark bars cross the segments at regular intervals, through the 

 first 7 segments; from the eighth segment and farther back the pale 

 intersegmental stripe of more anterior segments resembles a middorsal 

 pentagonal area. The same dark pigment extends over the upper part of 

 parapodia. The ventrum, dorsal and ventral cirri and everted proboscis 

 and setae are pale. 



The prostomium (PI. 5, fig. 1) is trapezoidal in shape, widest in back 

 when the proboscis is everted. The 4 eyes are in crescentic arrangement 

 with the anterior pair widest apart and the posterior pair slightly behind 

 and closer together. A median antenna is lacking; the paired antennae 

 are inserted at the frontal margin ; they have short cirrophores and 

 long, slender styles. 



Tentacular cirri number 8 pairs ; all may be long and slender but 

 were lost before the illustrations (PI. 5, fig. 1-2) were completed. 

 Dorsal cirri are long, slender, probably articled, with the first pair the 

 longest, and those of later segments proportionately shorter. Before 

 handling, the articles numbered 12 to 20, but the joints were subsequently 

 lost. Ventral cirri are also articled, but shorter than the corresponding 

 dorsal ones. 



The everted proboscis (PI. 5, fig. 1) is broadly flaring and ter- 

 minates distally in a circlet of many (more than 70) small papillae; 

 they are smallest at middorsal and midventral positions. Parapodia are 

 biramous (PI. 5, fig. 2) ; notopodial setae are smaller and shorter than 

 the corresponding neuropodial ones; the former are of a single kind, 



