214 
W. A. HASWELL. 
The second pair of nephridia (?r.) begin in both sexes close 
to the bases of the first pair of cirri, but dorsal to the latter; 
in some cases each appears to originate in a small contractile 
vesicle. From this point each runs backwards througli the 
rest of the second segment and through the whole of the third. 
In the male it bends inwards at a point nearly opposite the 
base of the second cirrus (third segment), and, after running 
inwards and backwards until it approaches very near its 
fellow of the opposite side, it bends shai’ply round on itself a 
little distance in front of the clasper. From the bend it runs 
forwards in close relation to its posteriorly running limb and 
on its outer side. The external opening of this nephridium 
has not been observed in the male. The cilia of the anteriorly 
running limb cease a little distance in front of half the interval 
between the first and second cirri, and the last cilia are a 
■considerable distance from the surface, so that the terminal 
part here, as in the head nephridia, would appear to be non- 
•ciliated or to possess cilia that are not usually in movement. 
In the female the second nephridium is continued further 
back than in the male, the loop or bend (fig. 7) occuiring 
nearly opposite the anterior paired part of tlie ovary. The 
anteriorly running limb of the loop runs throughout on the 
innei* side of the posteriorly running limb, quite close to the 
latter as seen in transverse sections, and opens on the exterior 
on the ventral surface near to, and a little in front of, the 
second cirrus. In one transverse series the part near the 
opening is loaded with a quantity of amorphous, opaque mattei*. 
The terminal part is a coiled non-ciliated tube. 
The third nephridia (?F.) in both sexes begin at the 
posterior end of the tail region. In line with each, behind 
the point where the lumen begins, is a row of four or five large 
nuclei, situated at the side of the rectum. It runs forwards 
on the ventral side between the nerve-cord and the intestine 
till it enters the trunk. In this position the vessel is quite 
distinct in thin sections (fig. 15). In the female the trunk 
part of the nephridium runs forwards on the dorsal side of 
the ovary to a point near the anterior extremity of the latter. 
