POLYCHAETOUS ANNELIDS FEOM PHILIPPINE SEA?. 627 



Avicula uncini with faintly serrated crest (fig. 5). Pennoned 

 setae comparatively large (fig. 6). 

 Collected from reef opposite Cebu. 



SABELLA SECUSOLUTUS, new species. 



Plate 52, figs. 7-13. 



Type. — Cat. No. 19013, U.S.N.M. Incomplete posteriorly, only- 

 four abdominal somites being present. Eight thoracic somites in- 

 cluding collar fascicle, the eighth being, however, thoracic in charac- 

 ter on the right side and abdominal on the left. Total length, not 

 including gills, 11 mm. Length of gills, including basal portion, 

 38 mm. Width of thorax, 5 mm. 



Collar low. widely separated on back (fig. 7) and split ventro- 

 lateral^ (fig. 8). Ventral ends prolonged into lappets overlapping 

 in the mid-line (fig. 8). Gills born on high basal portion, enlarging 

 just proximad to the base of the radioles (figs. 7-8). Radioles 26 on 

 each side joined by basal membrane 26 mm. in height. Membrane 

 region same color as rest of body — j'ellowish brown. Radioles lighter 

 and irregularly banded with reddish brown pigment. Tips of ra- 

 dioles naked for distance of 1.5 mm. No external appendages. No 

 e} r es. Tentacles 4 mm. in length. Distal portion attenuated and 

 pigmented reddish brown. The ventral surface of the head bears a 

 two-lcbed prominence which has been injured. It is merely indi- 

 cated in figure 8. 



Capillary setae of thorax of two kinds. First variety (fig. 9) 

 slender, without wing. Second variety (fig. 10) stout with prominent, 

 subterminal wing. Thoracic uncini avicular with serrated crest and 

 short basal portion. Pennoned setae (fig. 12) simple, spatulate, with- 

 out attenuated point. Capillary setae of abdominal region (fig. 13) 

 similar to second variety of the thoracic region but with narrower 

 wing and longer point. Abdominal uncini similar to those of thorax. 



Type collected at station D5113, Sombrero Island. 159 fathoms. 

 dark green mud bottom. 



Family HERMELLIDAE. 

 Genus TETRERES Caullery. 



TETRERES TREADWELLI, new species. 



Plate 52, figs. 14-23. 



Type. — Cat. No. 18964, U.S.N.M. Specimen in good condition and 

 complete anteriorly, but having only 2 mm. of the caudal region. 

 Total length, 26 mm.; width, 4 mm. 



Cephalic region greatly developed, being 7 mm. in length vent rally. 

 sloping down to 3 mm. in length dorsally. Peristomium deeply 



