106 Memoirs of the Indian Museum. [Vor. VI, 
I give a few details of the nephridial system in the anterior part of the body, as 
far as they can be made out by dissection under the binocular dissecting microscope. 
The subject has interested previous observers (cf. Beddard, 2, pp. 48, 655); the 
condition which I found differs, however, from that described by Beddard for what is 
presumably the same species, viz. P. corethrurus. 
It is necessary first to glance at the septa. The first is attached to the parietes 
at the level of groove 5/6; the second at 6/7, third at 7/8, and the fourth at the level 
of 9/10. It appears at first sight as if a septum is missing between 7/8 and 9/10: as 
will be seen, this is not the case; what has happened is that septum 8/9 has been 
shifted backwards! All the bone septa are thickened. 
The next septum is attached at the level of groove Io/II, and is thin; subse- 
quent septa are attached at subsequent grooves,—11/12, 12/13, 13/14, etc., and may 
be described as very thin. These may be taken as corresponding to the grooves at 
which they are attached ; it follows therefore that septum 0/10 has disappeared ; but 
since, as said above, septum 8/9 has shifted back, the hiatus appears to be situated 
more anteriorly. 
The justification for this view is the disposition of the nephridia. What is appar- 
ently segment x contains two pairs of nephridial coils, what is apparently the united 
segments viii and ix contains one only. The external apertures of the nephridia are 
near the anterior borders of their respective segments; and though the nephridial 
coil belonging to segment 1x has been pushed backwards by the backward shifting 
of septum 8/0, the external aperture has remained in its original position; so that 
the nephridial tube of ix has now, passing forwards, to pierce the (true) septum 8/9 
(the last thickened un) in a forward direction in order to arrive at its external 
aperture. 
The nephridia of segments viii, vii, and vi have their normal disposition. 
Those of v, lying deeply within the cone-shaped septum 5/6, debouch normally on the 
surface ; but the coils constituting their posterior ends, and lying by the side of the 
anterior end of the gizzard, are apparently connected with similar coils of the nephri- 
dia of iv and iii. I could not separate the posterior ends of these three nephridia; 
but whether they merely interlace, or whether they communicate, I cannot say. 
The external openings of the organs belonging to iv and iii have the normal position. 
The nephridium of segment ii forms a large and close coil on the side of the 
oesophagus, behind the pharynx and in front of the gizzard; from this there passes 
forwards a thick tube which enters the hinder end of the pharynx. This is a much 
more intimate and direct connection of nephridia and alimentary tube than that 
described by Beddard for P. corethrurus, where a nephridium opens on to the surface 
in segment ii, but owing to the great retractility of the anterior part of the body, 
this opening may actually at times come to lie within a temporary buccal cavity. 
