14 
The species seems to be rather closely related to 5. tenuicau¬ 
data Bastian, but it diverges so much in some respects that I do 
not venture to refer it to this species. First it is considerably 
smaller, the average size being about half that of Bastian’s spec¬ 
ies; secondly the æsophagus is somewhat longer and the tail 
considerably longer in proportion to the body-length than is the case 
n 5“. tenuicaudata. Also the supply of setæ in the front end is 
rather different in the two species. 
The shape of the body is siender and highly resembles that 
of Bastia n’s species. It is of about equal width during the greater 
part of its length. In the foremost half of the body it is taper¬ 
ing slowly towards the front end. In the hindmost half it is taper¬ 
ing in the same way unto the anal aperture. The tail is conical 
in its proximal half, then it tapers quickly, and the distal half is 
thin and of equal width until the tip, where it is somewhat ex- 
panded. The shape of the tail is much like that of 5. tenuicaudata , 
but in proportion to the body-length the tail of the Auckland-species 
is considerably longer. 
The cuticle is transversely striated and set with points. As d e 
Man States, these points are lacking on the head and irregularly 
spread behind the lateral organ; for the rest they are arranged 
more or less regularly in transverse striæ, except in the anal region 
where their arrangement also seems to be quite irregular. 
On the head is situated a crown of long and stout setæ, each 
accompanied by a somewhat smaller one, inserted immediately be¬ 
hind the large one. Besides these, long, fine hairs are seen spread 
over the surface of the body, especially in its foremost part. The 
lateral organ is spirated and, as in the foregoing species, it is 
larger in the male than in the female. 
The buccal cavity is cup-shaped and much like that of P. 
tenuicaudata. The æsophagus is somewhat swollen in its posterior 
end, but for the rest of about equal width. The nerve ring is rather 
indistinct; it is situated somewhat behind the middle, and, imme¬ 
diately behind this, the tube of the excretory giand opens. 
As to the ventral giand I shall only remark, that the duet is 
short just as in the preceding species, and the ampulla rather 
large. I am not able to State with certainty anything about the 
