542 PROCEEDINGS OF THE ACADEMY OF [Jutyj 



large swollen base which fills the anterior cleft, but the style is lost. As 

 noted above, the ceratophores of the lateral tentacles are the anterior 

 prolongations of the prostomiiim, which nearly equal and lie somewhat 

 ventral to the median tentacle; their st3des are slender, about 2h times 

 as long as the prostomial width, and taper to the tip without a subter- 

 minal enlargement. Comparatively very stout palpi crowd the peris- 

 tomial parapodia; they are coiLstricted at the base, then swollen and 

 again tapered to acute tips; their length is aljout ItV times the lateral 

 tentacles; each is marked longitudinalh' l)y a prominent broad ridge 

 and lateral impressed lines. 



The buccal parapodia are prominent and elongated, reaching directly 

 for\\ard far l^eyond the prostomium; they are swollen at the base, 

 deeply cleft at the end and bear no setce. The tentacular cirri have a 

 distinct subterminal enlargement tapering into a filiform tip. They 

 somewhat exceed the lateral tentacles in length. As usual in the 

 family the proboscis is stout and muscular. When fully protruded it 

 measures 21 mm. long, equalling the first 17 somites, and 7 nnn. wide 

 by 9 mm. deep. Its surface is strongly wrinkled and its end bears 16 

 soft papillae above and 16 below, all nearly fan-shaped and folicaeous 

 in this specimen, l:)ut probably collapsed. A pair of stout jaw-plates 

 abo^'e and below are suljtriangular, each bearing at the anterior angle 

 a blimt claw-like tooth followed on the lateral border by a dentinal 

 ridge. At the base of the proboscis, on the dorsal surface between 

 the bases of the palpi, is a single prominent tubercle. 



The peristomium is scarcely evident as a distinct ring, being com- 

 pletely united with the prostomium and succeeding somite. From the 

 dorsum of the latter (II) arises a prominent nuchal fold similar to but 

 larger than that of Halosydna gelaiinosa. It is subtriangular, attached 

 by its posterior border but otherwise free, and conceals the entire pos- 

 terior and middle ]3ortions of the head. It can be drawn forward 

 so as to cover much more than shown in the figure. 



Generally the segments are well differentiated and about 4 times as 

 Avide as long. The ne])hridial tuljercles are prominent, begin on somite 

 XII and project outward and baclcward. Parapodia are much elon- 

 gated, c^uite equalling f of the width of the boch'. The neuropodia are 

 strongly predominant, broad and truncate at the ends, with a pointed 

 somewhat membranous presetal lobe which conceals the end of the 

 aciculum. The notopodia are small and very slender; the}- arise from 

 the middle of the dorsal surface of the neuropodia and enclose a slender 

 aciculum. Dorsal cirri arise just above the notopodia, from large stout 

 bases having a prominent glandular lobe. Their styles are long, about 



