392 PROCEEDINGS OF THE ACADEMY OF [April, 



X. The only known specimen is a male filled with sperm represented 

 by the anterior 36 segments and measuring 11 mm. long and 2 mm. in 

 total width. 



Prostomium (PI. XXXIII, fig. 105) partly sunken into peristomium,its 

 profile nearly straight to ocular region where it bends downward rather 

 abruptly into the vertical anterior face; outline nearly circular, 

 truncate behind and slightly wider than long. Eyes black, two pairs, 

 situated close to median ceratophore, both visible from above, those 

 of each side nearly in contact and of the two sides separated by nearly 

 two-thirds of the prostomial width; the anterior pair at about the 

 level of the tentacular axis and twice the diameter of the posterior pair 

 which are dorsal. Median tentacle arising from a short ceratophore 

 not more than one-third of the length of the prostomium and dorso- 

 anterior in position; style about one and one-half times length of 

 prostomium, the basal two-thirds rather stout, the remainder rather 

 abruptly contracted into a filament with a slightly knobbed tip. 

 Tentacular lamellae thin, aliform, bilobed by a lateral notch, not longer 

 than ceratophore to which the medial border is broadily united. Lat- 

 eral tentacles united with dorso-median aspect of peristomial para- 

 podia, only their filamentous tips free, the rest concealed by the buccal 

 lamellae, to the lateral face of which they are united. Palpi arising 

 from distinct ceratophores appearing external to the peristomial 

 parapodia, the styles nearly flagelliform, slender and regularly tapered 

 to delicate tips, more than three times as long as the median tentacle. 

 All cephalic appendages lack cilia but are provided with a few regularly 

 arranged sensillae bearing minute sensory hairs projecting through 

 cuticular pores. 



Peristomium and its parapodia largely coalesced with venter of 

 prostomium, beyond which the latter project for half their length (Pi. 

 XXXIII, fig. 105), bearing at the distal end a dorsal and a ventral 

 tuft of capillary setae which spread anteriorly and cross in front of the 

 prostomium. Tentacular cirri with very short indistinct cirrophores, the 

 styles similar in form to the median tentacle, the dorsal nearly equal 

 to the latter, the ventral about two-thirds as long. Buccal or peris- 

 tomial lamella a thin curved plate attached to the medial side of the 

 peristomium and reaching slightly beyond its end. 



Metastomial segments rather well marked, except dorsally in the 

 pharyngeal region which is very smooth, about four or five times as 

 wide as long with well-marked ventral muscular ridges and between 

 them a neural groove. 



Parapodia strictly lateral, arising near ventral level, rather stout 



