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posed of fine muscle fibres. There is no chitinous inner 
lining as in Lepeophtheirus. Between the basement layer 
of the intestinal wall and the integument there is a net- 
work of muscles passing in various directions. This 
tissue represents the body-cavity and body-wall. The 
spaces between the muscles are filled with the red blood. 
The peristaltic movement of the intestine is similar to that 
observed in Lepeophtheirus. 
In the cyclops stage the mouth leads into a short, 
narrow cesophagus (@, Plate V., fig. 2), which passes into 
the comparatively wide stomach on its ventral aspect. The 
stomach is lageniform, with the narrow end pointing 
posteriorly. On the dorsal aspect, at the anterior end, it 
is produced into a short, blunt cecum. ‘The narrow end’ 
of the stomach connects with the intestine, a long 
straight narrow tube, greatly compressed over the region 
of the receptaculum semiinis. The intestine terminates 
in a very short rectum leading to the anus. The cells 
both free and attached along the wall of the stomach and 
intestine are similar to those in the adult. Sometimes 
the stomach is filled with free cells, which are kept con- 
stantly travelling backward and forward by the move- 
ment of the intestine. At other times few free cells can 
be seen. No trace of blood between the alimentary canal 
and the integument, as found in the adult, has been 
observed in the young. 
- No trace of a digestive gland could be found in the 
adult. In the young it is probably represented by a 
series of groups of cells running along the lateral margins 
of the cephalo-thorax (Plate V., figs. 1 and 3, l.v.). A short 
duct could be traced leading from these groups into the 
stomach, just posterior to its junction with the csophagus. 
When the alimentary canal of a living parasite is 
opened, and the free cells are isolated and examined with 
