ON A COLLECTION OF PARASITES FROM THE SOUDAN 609 
Behind the neck little or no distinction was, recognisable ,from 
one end of the body to the other. Whereas in the former region 
the greatest breadth was 3mm in:the body the breadth rarely 
exceeded 2m though. it gained in thickness. Without exactly 
seeing what caused it, these worms made an impression of untidi- 
ness and they were thrown into the most complicated coils and 
knotted together in an almost inextricable fashion. It took much 
time and patience to untie one for the measurement mentioned 
above. 
In section the head is rectangular with rather salient ae 
The lateral diameter at the extreme end is.but little greater than 
the dorso-ventral but as one passes backward this proportion 
increases unlil the space from side to side is much greater than 
from above downwards. LPS 
The single median sucker is, very le and soon D 
as one traces the sections backward. It looks more like a relic than 
a functional part. Around its inner, end, are four minutes nerve 
masses which in a section or two further back have become.a 
nerve band and this again still further back resolves itself into two 
longitudinal nerve cords. Lying just, within each nerve cord is a 
very fine duct the. most anterior extension of the water vascular 
system. The two ducts approach each other as the head diminishes 
in size but [ could not definitely see if they pass into each other 
though [I expect they do. Each is lined by a stout ie and sur- 
rounded by a definite ageregation of cells. 
The cuticle is thick and well defined over the anterior end of. the 
body but posteriorly it is relatively much thinner and less conspi- 
cuous. Inits better developed regions the cuticle is clearly two 
layered but J was unable in any way to make out more about it. 
Within the cuticle in a few favourable. sections a row of dots may 
be seen immediately underlying it and in all the sections, though 
most clearly ,in those from the anterior region, ihe oval bodies of 
the epithelial. cells can be detected lying: ‘a little distance wilhin 
the cuticle.. DR PEN : Rob 
The CU ne 1s peculiar, Hana à as ne pierces the 
parenchyma in all directions but shows no kind of arrangement 
into systems. A few small:transverse and oblique fibres crossthe 
body but byfar the larger portion oftle museular tissué, is contained 
Î 
