340 THE ANNELIDA POLYCHAETA. 



The type is incomplete posteriorly. The part present consists of fifty-one 

 somites. It is 26 mm. long and has a maximum width, exclusive of the para- 

 podia, of 3.4 mm., and inclusive of the parapodia, of nearly 5 mm. The body 

 is widest at and immediately caudad of about the eighth somite. Cephalad 

 of this the body is rounded, somewhat Uke the frustrum of a cone with the 

 truncate end narrow. Caudad the body narrows continuously and much more 

 gradually. 



The principal portion of the prostomium in outline as seen from above is 

 semicircular, the anterior margin being strongly convexly rounded. It is deep 

 dorsoventrally, with the ventral portion much narrower than the dorsal. There 

 is a very large, circular, black ocular area, or eye, on each side just in front of the 

 posterior paired tentacle, the diameter of which it exceeds, and a much smaller, 

 longitudinally elhptic eye just mesad of each posterior paired tentacle. On 

 the ventral side are two thick, somewhat conical, bodies extending from the 

 bases of the palpi caudad to the mouth; they are contiguous and are distally 

 free as conical projections. Two pairs of distinct appendages are present in 

 the type. Each of the anterior pair, ordinarily interpreted as palpi, is attached 

 on the ventral surface in the angle between the ventral lobes above mentioned 

 and the ventral projection of the prostomium. The two palpi are separated 

 by less than their diameter, being unusually thick. Each tapers strongly distad 

 and is at present transversely wrinkled, or jointed, so as to appear to consist of 

 rather numerous short articles and a distinct terminal lobe such as present in 

 various other species. The tentacles, which are of about the same length as the 

 palpi, are much less stout and are cyhndrical. Each is set deeply in an excava- 

 tion in the caudolateral region of the prostomium and extends dorsad. Each 

 is attenuated, but more gradually so than the palpi, and is strongly transversely 

 wrinkled or jointed, the joints numerous. At present they extend only to the 

 fifth somite but appear to have contracted considerably in preservation. A 

 nuchal tubercle shows in the median line above under the projecting border of 

 the peristomium. 



The peristomium is about equal in length to the prostomium and is much 

 longer than the second somite. On each side it presents a lobe anteriorly partly 

 separated off above and below by a sulcus, this lobe abutting dorsally against 

 the posterior paired tentacle and in front against the anterior paired appendage. 

 On the ventral side it is deeply excavated semicircularly, leaving the portion 

 caudad of the mouth as a narrow band. The border caudad and laterad of the 

 mouth strongly radially furrowed or wrinkled. 



