NO. 3575 BATHYAL POLYNOIDS — PETTIBONE 7 



median antenna with ceratophore inserted on anterior part of pro- 

 stomiuni; lateral antennae inserted on anterolateral extensions of pro- 

 stomiimi (i.e., lepidonotoid) ; with paired long antennal sheaths dorsal 

 to lateral antennae. Tentacular segment (I) achaetous, with 2 pairs 

 tentacular cirri, with paired long tentacular sheaths between palps 

 and tentacular cirri, with bulbous facial tubercle between bases of 

 palps. Buccal segment (II) with parapodia rudimentary, achaetous, 

 with paired, long, ventral buccal cirri and first pair dorsal elytrophores. 

 With lamellar papillae on ventral hp and ventral bases of parapodia 

 on segments 2 and 3. Elytra or elytrophores more than 20 pairs (23) , 

 arranged on segments 2, 4, 5, 7, then on alternate segments to 23, 

 and then on every third segment to end of body. Parapodia very 

 long, subbiramous; notopodia small, with digitiform acicular lobes, 

 achaetous; neuropodia with elongated acicular processes. Neuro- 

 setae numerous, forming brushlike bundles, transparent, fragile, in- 

 flated and flattened distally, with faint spinous rows and tapered tips. 



Bathyadmetella commando, new species 



Figures 3, 4 



Material examined: The species is represented by a single damaged 

 specimen, collected in a trawl haul, southwest of the mouth of the 

 Cohmibia River, Oregon, 45°45' N, 125°09' W, 900 fms, 2.6° C 

 bottom temperature, 34.3727oo salinity, May 29, 1964, M/V Com- 

 mando, M. S. Alton, collector. The holotype is deposited in the 

 U.S. National Museum (USNM 33419). 



Description: Length 55 mm, width of body 6 mm; width including 

 parapodia 24 mm, including setae 34 mm; segments 58, last few small. 

 Body widest in middle, tapering gradually anteriorly and more so 

 posteriorly; flattened dorsoventrally; with extremely long parapodia. 

 Integument thin, delicate. Body reddish brown, darker on parapodia 

 and distal halves of elytrophores, lighter ventrally. Elytra all missing ; 

 elytrophores elongated, inflated basally, 23 pairs, arranged on seg- 

 ments 2, 4, 5, 7, then on alternate segments to 23, and then on every 

 third segment to end of body. Dorsal tubercles on cirrigerous seg- 

 ments thin walled, inflated, continuous as low ridges to cirrophores 

 of dorsal cirri; styles of dorsal cirri all missing. 



Prostomium (figs. 3a, 6) bilobed, wider than long, with paired very 

 large bidging eyes occupying most of posterior half of prostomium; 

 eyes with semicircular, dark purplish pigmented cups basally. Cer- 

 atophore of median antenna short, cylindrical, on anterior border 

 prostomimn; style missing. Ceratophores of lateral antennae long 

 cylindrical extensions of anterolateral borders of prostomium; styles 

 long, slender, with slight subterminal enlargements and slender tips. 

 Paired elongate antennal sheaths dorsal to the lateral antennae, wider 



