260 PROCEEDINGS OF THE ACADEMY OF [^lay, 



XXX, and more rapidly to the anal somite. The fifteen pairs of 

 elytra are borne on the same somites as in Harmothoe imbricata and 

 allied forms. 



The head (prostominm) is about two-thirds as long as broad, with 

 the greatest width at about the middle. Anteriorly it is divided 

 into two broadly rounded lobes by a median fissure which reaches 

 a.s far as the posterior eyes; laterally it is strongly and posteriorly 

 slightly convex, but normally the posterior margin is concealed by 

 a median nuchal lobe of the succeeding somite. There are no 

 anteriorly produced cephalic peaks. 



Eyes, two pairs, conspicuous, black, circular, the posterior only 

 visible from the dorsum. The anterior the larger, and situated on 

 the ventro-lateral faces of the head about their own diameter from 

 the anterior margin. The posterior dorsal close to the nuchal 

 margin and separated by an interval of four times their diameter. 



Exclusive of its base, which arises from the frontal fissure, the 

 median tentacle has a length of about two and one -half times the 

 width of the head, with a subterminal enlargement and a filamen- 

 tous tip of about one-fifth its length. Except on the latter it bears 

 rather long scattered cilia. The lateral tentacles arise from short 

 and slender ceratophores from the anterior surface of the bead at a 

 lower level than the median tentacle, but, in the absence of ante- 

 rior peaks, not very sharply demarcated from the cephalic lobes. 

 Their diameter is about two-thirds, and length slightly more than 

 one-half of the median tentacle. They are slender and taper con- 

 tinuously from base to apex, which is tipped by a delicate filament. 

 A very few cilia similar to those on the median tentacle are present. 

 Palps robust, with a basal diameter of rather more than one half 

 the width of the head and a length about equal to the median 

 tentacle. They taper rapidly, but not uniformly, to the acute tip, 

 which bears a short filiform appendage. Numerous short, truncate 

 cilia are borne on five longitudinal lines, of which two are nearer 

 together on the medial aspect and the others respectively dorsal, 

 external and ventral. Tentacula?* cirri similar to the uotopodial 

 ■cirri, ciliated like the median tentacle; the dorsal is slightly the 

 longer. 



Somite I is very narrow dorsully, but bears an unusually promi- 

 nent median lobe which overlaps the head between the posterior 

 "eyes. The nephridial papillte become distinct on IX, and continue 



