298 PROCEEDINGS OF THE ACADEMY OF [April, 



diameter which may belong to this species. The parapodia bear large, 

 semierect respiratory postsetal lobes as in A. spinifera Moore and also 

 possess the conspicuously protruding spine and the winged and toothed 

 setse of that species, though the latter are less distinctly geniculate. 



Station 4,351, off Point Loma Lighthouse, Monterey Bay, 423-488 

 fathoms, soft green mud. 



Drilonereis faloata sp. now PI. XX, figs. 150-154. 



A typical member of the genus known from incomplete worms 

 only. The type consists of an anterior piece of 188 segments, and a 

 posterior of 41 segments, possibly belonging to the same individual, 

 the middle region of which is wanting. Together the pieces measure 

 121 mm. long and have a maximum width of 1.2 mm. and a depth 

 practically the same. Form linear, terete. 



Prostomium elongated, ovate-elliptical, one and one-half or more 

 times as long as wide, strongly depressed, the depth about two-fifths 

 width, the greatest width being at the posterior end where the prosto- 

 mium is mortised into the peristomium. No distinct nuchal organs 

 or longitudinal grooves and no eyes above; a shallow median longitu- 

 dinal groove below. 



Peristomium and II achsetous, about equal above and together 

 about two-thirds as long as prostomium. Peristomium broadly 

 excavated for half its length above for the insertion of the prostomium, 

 produced forward below to form a prominent but simple bilobed 

 lip, not sharply differentiated from the small palps. 



Body segments of nearly uniform diameter, subterete or slightly 

 depressed, the venter very slightly flattened, very firm and wiry 

 anteriorly, softer behind. Segments sharply defined and very regular, 

 simple anteriorly, biannulate behind, generally about one-half as long- 

 as wide, but exceeding this in middle region. Close to the caudal 

 end the segments are abruptly contracted and depressed. Pygidium 

 a minute ring, bearing four short, conical, equally divergent cirri. 

 Cuticle very smooth, polished, iridescent. Color nearly uniform 

 purplish-brown. 



Parapodia (Pi. XX, figs. 150, 151) are set into slight lateral de- 

 pressions and project straight out. Anteriorly (fig. 150) they are 

 nearly as long as the segments, but gradually become smaller simul- 

 taneously with the elongation of the segments until they are only 

 one-third as long, though near the caudal end they are again relatively 

 longer. All are simple, short, truncated, cylindroid, setigerous 

 tubercles with a small dorsal steplike tubercle representing the 

 notopodium and a somewhat ventral, papilliform postsetal lobe which 



