I9I4-J J- Stephenson : Oligochaeta. 375 



The last hearts are in ix. 



The testicular sacs are of moderate size^ rather rectangular 

 in shape, in segment x, attached to and depending backwards 

 from septum /It. Each sperm-duct is a fine tube, which forms a 

 relatively immense close-packed coil, larger than the testicular 

 sac ; it occupies a portion of segments ix and x, lying in front of 

 the sac in ix, and on its outer side, to which it is applied, in x. 

 Its great length reminds one of the description given by Bourne 

 (i) of the duct in D. grandis ; it must be at least as long in this 

 species, relatively to the smaller size of the animal. The duct 

 enters the prostate at a point which would be, in the natural 

 condition of the parts, at the upper and posterior part of its inner 

 surface (on its upper surface, towards its posterior end and near 

 the outer margin, as the specimen lies pinned out). 



The prostate is oval in shape, with its long axis antero- 

 posterior, cushion-like, sessile on and firmly attached to the body- 

 wall ; its surface is shining, due to distinct bundles of longitudinal 

 muscular fibres, and its anterior half is again covered over by a 

 separate layer of transverse muscular bundles. It is situated in 

 segment x (reckoning by the septa) : but it corresponds externally 

 to segment xi, overlapping furrow IV only by its anterior end; 

 septum TT is bulged backwards by it, and is attached to the body- 

 wall round its posterior end. 



The ovaries are of considerable size, massive, not branched or 

 folded, and are situated in an ovarian chamber which also contains 

 the nephridia of segment xi, and out of which open the egg-sacs. 

 The chamber arches over the alimentary canal; its limits are 

 defined dorsalh^ by the fusion of septa y-i and \l ; this fusion takes 

 place, not at the insertion of the septa into the dorsal body- wall, 

 but along a line some distance below this, between their parietal 

 insertion and the alimentarj'' tube. Between this line of fusion 

 and the dorsal body-wall the two septa are not fused, but merely 

 adherent, and can be separated without tearing. 



The egg-sacs are elongated, with irregular bulgings; thev 

 extend backwards into segment xiv, where they bend inwards 

 and slighth^ overlap in the middle line. Septa li and {i are fused 

 together round the stem of the sac where this passes through 

 them; the sac is narrow in xiii, swelling out just behind if. 



The ampulla of the spermatheca is subspherical in shape, and 

 is situated under the arch of the nephridium on the posterior face 

 of septum i, to which both it and the nephridium are attached. 

 The duct is thin and moderately coiled ; it passes down the 

 posterior face of the septum to the body-wall, and piercing the 

 septum enters segment vii; its extreme terminal portion becomes 

 a little stouter and firmer, and joins the atrium at its base. The 

 atrium is an oval sac, which lies on and partly in the body-wall of 

 segment vii, its free rounded end directed forwards ; the length 

 of the atrium is about half that of the segment in which it 

 lies. 



