1915.] J. STEPHENSON : Indian Oligochaeta. 58 
Prostomium prolobous,—an oval lobe filling up the circle of the anterior margin 
of the first segment. 
The setae are paired, but not very closely in the anterior region; in the segments 
near the male aperture aa=34ab, further back aa=6ab. The other relations may be 
given as aa=bc, dd=half circumference. The setae begin on segment ii. 
No clitellum is distinguishable. The sexual apertures also were distinguished 
only doubtfully, though the specimen was quite mature; they all were extremely 
minute, the male pores apparently in db, the female as whitish spots in a, the sperma- 
thecal apertures in c, in the usual furrows. 
Genital markings were present as follows (fig. 7): —-On segments x and xi, bisected 
by furrow 10/11, is a transversely oval area, which extends antero-posteriorly from 
the setae of x to those of xi, and laterally on each side to a point outside the line 0D. 
Thus in lateral extent it comprehends the whole ventral surface; while antero-pos- 
teriorly it is more than the equivalent of a segment, since the ventral setae of x are 
in front of, and those of xi very considerably behind, the middle of the length of their 
respective segments. The margin of the area (b) is white, the interior(c) darker. 
Within the dark region, medially situated on the posterior half of x, is a semicircular 
raised patch (e) with its base lying at furrow 10/11; the furrow is here slightly curved 
with its convexity backwards, and this portion of the furrow is deepened as compared 
with the portions in proximity to the lateral margins of the raised semicircle, which 
are shallow (d). 
A slightly thickened lighter oval area, also transversely elongated, is present on 
segments vii and viii, bisected by furrow 7/8; it is however less well marked and less 
extensive than that on x - x1. 
Internal anatomy.—Septum 5/6 is moderately, septa 6/7—8/9 are considerably 
strengthened. 
The gizzards are three, in segments xiii—xv; this region might be described as a 
fortified part of the oesophagus; it is not very hard, there is not much constriction at 
the septa, and the septa are not displaced at all. 
The last heart is in ix. 
The nephridia arch round the gut on each side, each nephridium being adherent 
to the posterior face of a septum. The nephridiopores are (? always) in the line of 
the lateral setae. 
The testis-sacs are large, suspended by septum 9/10 and slightly constricted by it. 
The portion of the sac which projects forwards into ix is larger (considerably larger 
on the left side) than that which projects backwards into x. After opening one of the 
testis-sacs and clearing out the detachable flocculent matter, a quantity still remained 
intimately adherent to the sac-wall as a sort of fur; this perhaps indicates that the 
testis is a diffuse proliferation of the wall. The site of the funnel was perhaps indi- 
cated by a small iridescent mass on the floor of the sac in the neighbourhood of the 
septal attachment, where the vas deferens could also be seen arising. The vas 
deferens undergoes a number of windings on both sides of the septum ; it enters the 
prostate on its anterior face at about the middle of its height. 
