STUDIES ON THE DIGENETIC TREMATODES. 445 
in the neighbourhood of the ventral sucker. ‘The myoblasts 
of the subcutaneous muscles are numerous, and arranged in 
groups. ‘Their nuclei measure ‘004—005 mm. 
The oral sucker is subterminal and nearly round, measuring 
17-28 mm. ‘The ventral sucker is situated very nearly in 
the middle of the body and is transversely oval. Its long 
axis measures ‘41—"58 mm., its short axis 31-48 mm. It is 
thus about twice the size of the oral sucker, and the trans- 
verse diameters of the suckers are respectively about one 
tenth and two ninths of the body-length. The internal 
structure of the suckers offers nothing peculiar. 
The pre-pharynx is distinct and rather wide. The pharynx 
is of comparatively large size, measuring *15~21 mm. in 
diameter. It is nearly globular, but the breadth is shghtly 
greater than the length. It is proportionately much larger 
than it is in any other member of the ALLocrEADUNE. ‘The 
cesophagus is about as long as, or a little shorter or longer 
than, the pharynx (‘1-18 mm.). In section it is transversely 
oval. The intestinal bifurcation occurs almost midway 
between the suckers. The diverticula are fairly wide (‘04— 
‘07 mm. in a large specimen). They pass round the sides of 
the ventral sucker and, taking up a dorsal position, extend 
nearly to the posterior end of the body. ‘The cesophagus is 
sharply differentiated from the diverticula, not only by the 
change in the nature of the lining, but also by a well- 
marked constriction (fig. 10). The bifurcation is of the 
nature of a dilated sac formed by the fusion of the initial 
parts of the diverticula. In appearance it rather simulates 
a small ventricle. The pharynx and cesophagus are lined 
with a cuticular membrane; that of the former is probably 
true cuticle, that of the latter is transformed epithelium. In 
any case the two are not identical, for the pharyngeal lining 
is thicker and stains more deeply than the cesophageal. The 
bifurcation and diverticula are lined throughout by a well- 
developed epithelium, the nuclei of which are round and 
measure ‘0052 mm.. Numerous hair-like processes are given 
off from the cells. The musculature of the alimentary canal 
