46 Memoirs of the Indian Museum. [Vor. VI, 
(instead of further back in xv, xvi, or xvii). The dorsal vessel also seems to begin 
variously in xii, xiii, or xxli; there appears to be no doubt about the last observation, 
and, since the previous account of the worm gives the origin of the vessel as xv, xvi, 
ot xvii, we may conclude that this character also shows a large degree of variation 
There are four well-marked lateral vascular commissures in the anterior region; 
the first, running very obliquely downwards and forwards, ends ventrally at a level 
between the setae of segments ii and iii; the second, less oblique, ends between the 
setae of iii and iv; the third, almost vertical, ends behind the setae of iv; the last, 
behind the setae of v ; they seem therefore to belong to segments ii—v. The ventral 
vessel is formed by the union of two trunks from the anterior end of the animal; this 
union takes place just behind the level of the setae of segment iv; the first two com- 
missures therefore join the trunks before their union, the last two join the ventral 
vessel. or 
The form of the nephridia is illustrated in fig. 2a and b. The interest here again 
lies in the variability of characters which are commonly taken to be of specific value; 
and it may be noted that in this case the variability exists within the same specimen. 
Fig. 2a represents the nephridium of segment ix; it is thin, elongated, continued 
behind without sharp demarcation into the duct; fig. 20, from a nephridium behind 
the genital segments, is pyramidal, with a relatively narrow duct which leads off from 
the ventral and posterior angle with an arched course downwards and backwards to 
the surface (the arching was considerably more marked in another case). The figures 
were drawn from an entire specimen in cedar oil; the facts were also confirmed by a 
subsequent examination of longitudinal sections. 
The sperm-sacs and testes present the same features as the previous specimens from 
the Chilka Lake; but in one of the specimens which was sectioned the wall of the sac 
appeared to be wanting in its posterior part, and there also seemed to be a gap at one 
place on the antero-dorsal part of its extent. The contained sperm-morulae were 
nevertheless not scattered through the adjacent segments, but remained compacted 
together in a definite mass within the sac. Ripe spermatozoa were seen in clusters 
round the mouth of the funnel. The sac-wall is an extremely delicate structure, and 
it is of course possible that the apparent rents in its continuity are due to damage 
during section-cutting; I have, however, no reason to think that this is really so,— 
and of course a disintegration of the sac is the easiest way of explaining how the male 
products reach the funnel. 
The penial bulb is a small approximately spherical cluster of cells surrounded by 
a membranous capsule ; it might be called rudimentary. The cells of which itis com- | 
posed have no very distinctive characters; muscular strands pass upwards, as usual. 
The penial lumen is chitin-lined ; the bulk of the bulb, and the terminal portion of the 
vas deferens lie to its inner side. The male aperture can be seen on the surface as a 
semicircular slit, in the position of the (absent) ventral setae of xii. 
What I think must be regarded as a rudimentary female funnel and oviduct were 
discovered in longitudinal sections. A few nuclei are seen on a slight backward 
pouching of the ventral portion of septum 12/13 in one of the series; and from this 
