546 PBOCEEDtNGS OF THE NATIONAL MUSEUM. voL.xxt. 



Family GLOSSIPHONIDyE. 

 PROTOCLEPSINE, new genus. 



This genus exhibits primitive external characters in the retention of 

 the full number (3) of annuli in all of the anterior somites, and in the 

 elevation of the eyes upon papilhu which stand in serial relation to the 

 dorsal median segmental papilhc of the succeeding somites. The sex-' 

 ual pores occupy the usual positions in somites X and XI. 



The type species has three pairs of eyes situated on somites I, II, 

 and III; and the posterior somites XXII to XXVI are reduced. 



I. PROTOCLEPSINE SEXOCULATA, new species. 

 (PJate XL, fig. 1.) 



Unfortunately there is but a single much contracted specimen of this 

 interesting species. The prostomium is curled ventralward and the 

 specimen is probably immature, so that the following measurements 

 have a relative value only : 



mm. 



Length 5. 1 



Greatest width (XlXth somite) 2.5 



Depth at somite XLX 1.2 



Width at genital region 2.2-2.4 



Depth at genital region About 1 



Diameter of acetabulum 1.5 



In its contracted condition the body is truncated at both ends, the 

 prostomium being curled under at the anterior end (corrected in the 

 drawing, tig. 1), and the acetabulum drawn closely up at the posterior 

 end. Consequently the body appears almost quadrate, with its greatest 

 width far back. It is strongly convex above and slightly concave 

 below. The acetabulum is large and circular, with thickened mar- 

 gins. The anterior sucker is wide, witli thickened crenulated margins, 

 formed posteriorly by aunulus 5; its interior and the mouth opening 

 are hidden by the infolded prostomium. A deep median and three pairs 

 of small lateral sulci divide the fiee margin of the prostomium into 

 eight lobes, of which the four middle ones bear as many small papillae. 

 Dorsally it consists of a larger anterior and a smaller posterior annulus. 



The somites I to XXI, inclusive, are complete, each consisting of 

 three annuli; XXII and XXIII are biannulate; XXIV and XXV 

 biannulate at the margins and undivided mesially ; and XXVI consists 

 of a single annulus. On each side of the middle line are three series of 

 dorsal and four series of ventral papilhe, situated on the first annulus 

 of each somite on which alone papilhu arc evident. Of the dorsal series 

 the innermost are widely separated, leaving a broad median area; the 

 outermost are supra-marginal, and the remaining series halfway 

 between these. All of the i^apilhi' are smooth and rather inconspicu- 

 ous. On the first, fourth and seventh rings behind the prostomium 



