60 Records of the Indian Museum. [VoL. V, 
segments; many were, however, preparing for fission, and one of 
these showed seventy-nine in its anterior and ninety-one segments 
in its posterior half, or 170 altogether. In addition to the segments 
recognizable as such, there is always a posterior tapering region of 
the body where growth is apparently taking place actively, and 
where distinct segments have not yet been differentiated. 
The prostomium is bluntly conical in shape, and is well 
marked, though by no means so large relatively as is figured for 
Branchiodrilus (Bourne, loc. cit., fig. 1). There are no eyes. The 
first few segments, as far as the first gills, form a region of the body 
which is in preserved specimens somewhat narrower than that 
which succeeds it, though this is not obvious in the living and 
moving animal; indeed this region may then appear somewhat 
swollen. A peculiarity noticed on a number of different occasions 
was that when after a somewhat prolonged examination a Specimen 
died and began to disintegrate under the microscope, this latter 
process began by a shrivelling up of the region of the first ten 
gills, this region of the body becoming wrinkled and much narrower 
in diameter than before. | 
The anterior portion of the body is pigmented (plate vii, 
fig. 2), the prgment being black and occurring in granules more or less 
closely aggregated. On the dorsal surface there is a blotch of pig- 
ment about the level of the mouth, just in front of the level of 
the cerebral ganglion, and there are a few scattered granules to- 
wards the tip of the prostomium. A segmental distribution of the 
pigment is hardly to be recognized in segments ii-iv; but after this 
it is distributed as wéll-marked transverse bands one in each seg- 
ment. ‘These bands become less dense as one proceeds posteriorly, 
and after about the twentieth segment are inconspicuous; scat- 
tered pigment spots occur for some distance further, but these, too, 
ultimately disappear. On the ventral surface the appearances are 
more variable; there may be well-defined segmental bands here 
also, or there may be only scattered spots; but in any case the 
pigment is less than on the dorsal surface. 
The segments are delimited externally by a fairly well-marked 
annulation. 
The branchial processes are dorso-laterally situated hollow pro- 
jections of the body-wall, cylindrical in shape, longest in the 
anterior part of the body, and gradually diminishing posteriorly. 
The first of these processes are situated on the sixth segment as a 
rule, but occasionally on the fifth. It is not always easy in the 
living and moving worm to be certain of the exact numbering of 
the segments; and I therefore examined a number of individuals 
fixed and mounted in balsam; in nine such specimens the gills 
began in segment v in one, in vi in the rest. 
The first gill on each side is a little shorter than the second; 
when turned forwards these reach well in front of the tip of the 
prostomium. The branchial processes of the anterior part of the 
body are easily visible to the naked eye, and are over a millimetre 
in length; the longest I have measured was 16mm. After the 
