116 
Queensland Trematodes 
oesophagus is about 025 mm. long. The intestinal bifurcation occurs 
just in front of the cirrus-pouch and the wide diverticula extend to 
near the tip of the tail. They are almost entirely obscured by the 
yolk glands. 
The excretory vesicle bifurcates dorsal to the posterior testis. 
The genital aperture is situated a little in front of the ventral sucker. 
The cirrus-pouch is of comparatively large size and extends well past 
the middle of the ventral sucker. It contains a very large vesicula 
seminalis, which is divided into a large oval proximal part and a smaller 
globular distal part. It fills the greater portion of the pouch. The 
pars prostatica is small and globular and the ductus is short. 
The testes are very large and fill almost the whole of the post- 
acetabular region. Their position is somewhat inconstant. In some 
cases the anterior testis touches the ventral sucker; in others it may be 
as much as 0'2 mm. behind it, the average being probably about 0T5 mm. 
The post-testicular space varies correspondingly (025 to 035 mm.). 
The testes are of somewhat irregular shape but, roughly, the anterior 
one is transversely oval while the posterior is somewhat heart-shaped 
or trilobate, the apex being directed backwards. They are always 
closely opposed and may even overlap. Their size varies but is generally 
about 0'45 x 065 mm. 
The ovary is also variable in position. Usually it is crushed in 
between the ventral sucker and the anterior testis, both of which it 
overlaps. It is generally on the right side. In some cases, however, 
it lies entirely dorsal to the anterior testis and may be displaced back¬ 
wards some considerable distance. In such cases the anterior testis 
usually touches the ventral sucker. The ovary is a small globular or 
ovoid body measuring 0‘ 16 x 02 mm. There is no receptaculum 
seminis, but the initial part of the uterus is filled with sperms. The 
yolk glands are very extensive, extending almost the whole length of 
the body from the level of the pharynx to the tip of the tail. They are 
chiefly lateral, but in the neck they form a continuous dorsal layer 
between the pharynx and the middle of the ventral sucker. They 
overlap the testes to some extent but they do not unite in the post- 
testicular space. The eggs are very scanty, the greatest number in 
any one specimen being 18. They measure 0’086 to 0T91 x 0049 to 
0’055 mm. the average being 0’089 x 0’053 mm. 
This species bears an extremely close resemblance to E. bursicola 
(Crepl), so close indeed that the specific differences are extremely minute. 
In the first place, however, the habitat is different. E. bursicola 
