386 THE ANNELIDA POLYCHAETA. 



branchiae on any somites. No eyes. With a series of lateral sensory pits as 

 in Travisia. 



Pygidium small, cylindrical, longitudinally furrowed. 



Segments not numerous (twenty-eight in the type). 



Genotype. — Kesun fusus, sp. nov. 



Separated from Travisia by the complete absence of cirri. 



Kesun fusus, sp. nov. 

 Plate 67, fig. 5; Plate 68, fig. 1, 2. 



Body pointed at both ends, with the intervening region cylindrical, or 

 slightly thicker anteriorly than posteriorly. The type is 14 mm. long with a 

 maximum thickness of 2.5 mm. There are twenty-eight setigerous somites. 



The prostomium is a small, wholly smooth process which is narrowed 

 cephalad subconically, but is distally blunt. It is slightly compressed dorso- 

 ventrally. (Plate 68, fig. 1). 



The peristomium strongly widening from the prostomium caudad. It is 

 composed of three incomplete annuli. The surface is granular or finely vesicular, 

 the vesicles being small and with those along the caudal edge largest. On each 

 side there is the usual nuchal groove, this being deepest at its caudal end. (Plate 

 68, fig. 1). 



The second somite is biannulate. Each annulus bears a single row of fine 

 but distinct vesicular papillae, with in front of this smaller and more or less 

 obscure ones. (Plate 68, fig. 1). The succeeding somites to and including the 

 fifteenth are triannulate. The sixteenth, seventeenth, and eighteenth somites 

 are biannulate, the two latter incompletely so laterally. The remaining somites 

 are uniannulate, or with two or three of the most anterior of them with vague 

 indications of subdivision. All annuli with a single row of well-formed but 

 very small papillae, the granules in front of this row smaller and inconspicuous. 

 All the annuli of somites of the anterior and middle regions are very short. 

 The undivided posterior somites are considerably longer than the annuli of the 

 anterior somites, but are shorter than the entire somites. (Plate 68, fig. 2). 



Neither notopodial or neuropodial cirri or branchiae at all indicated on any 

 of the segments. 



Fascicles of setae small, in two rows. On the anterior somites the fascicles 

 arise from the apices of distinct processes, or papillae, of about the same size or 



