ON BENHAMIA C(EOIFEEA, N. SP. 105 



each side are connected by a longitudinal groove, as in other 

 species of the genus. But what marks this species as distinct 

 from all others hitherto examined is the presence and arrange- 

 ment of numerous small pits, no doubt having some function 

 in relation to copulation. The figures give a better idea of the 

 arrangement of the pits than any detailed description. It will 

 be seen that for the most part they form transverse rows on 

 Segments xv, xvi, xvii, xix, xx, xxi, xxii. There is a single 

 median pit on Segment xxiii, and on the 18th segment 

 three short longitudinal rows occur, one median and a pair 

 of lateral rows. 



"Copulatory organs" (" pubertats Tuberkeln") have been 

 noted by Michaelsen in various species, especially B. affinis 

 and B. inermis. In the latter they are paired, and occur on 

 segments in front of the clitellum, but they appear from his 

 figures and descriptions rather as tubercles than as pits, and 

 have altogether a diflferent arrangement. 



These pits in the present worm mostly have a well-defined 

 margin, not raised above the general level of the surface. In 

 others there appears to be a papilla on one side of the pit, pro- 

 jecting to a greater or less extent into the cavity of the pit, as 

 shown in fig. 2, B. C. But in no case do the papillae project 

 to the exterior, nor are they visible except on careful inspection. 



Two pairs of similar pits occur in relation to the sperma- 

 thecal pores, viz. on Segments vii and viii (fig. 1, p^. p^.)- The 

 anterior pair lies on the hinder margin of the segment, the pos- 

 terior pair on the anterior margin of the second annulus — this 

 one is more laterally placed than the former. In the opened 

 worm there were no sacs or other structures projecting into the 

 cavity of the worm's body ; the pits appear to be limited to the 

 body wall. 



The spermathecal pores have the usual position on the 

 boundaries of Segments vii-viii and viii-ix, in a line with the 

 inner series of chsetse. 



The oviducal pore is small, but it is visible just in front of 

 the ventral (inner) chsetae of Segment xiv. On Segment xiii 

 a pair of circular whitish areas, each with a central depression. 



