30 
Trematodes of North Queensland 
pointed. The cuticle is thickly beset with stout spines, which cover 
the whole body to within a short distance of the tail. 
The oral sucker is almost terminal and measures 0-18 mm. In one 
specimen it was found retracted within the body almost to the level 
of the ventral sucker. The inconspicuous ventral sucker is situated 
a third of the body length from the anterior end and measures 
0-10 X 0-13 mm., being somewhat transversely oval. 
The prepharynx is almost absent. The small globular pharynx has 
a diameter of 0-07 mm.; the oesophagus is slightly longer (0-1 mm.). 
The intestinal diverticula are narrow and extend to within a short 
distance of the tip of the tail. The genital aperture is median and a 
little in front of the ventral sucker. The comparatively large cirrus- 
pouch bends round the right border of the ventral sucker and extends 
about 0-1 mm. behind it. Its total length is over 0-4 mm. and its 
greatest width about 0-15 mm. It contains a small ovoid vesicula 
seminalis, a long pars prostatica and a short wide cirrus. No spines 
could be detected on the cirrus, but from analogy with other species of 
this group it is probable they are present. 
There is a large vaginal sac, with thick walls, extending from the 
genital aperture, on the left side of the ventral sucker. It measures 
0-25 X 0-13 mm. The uterus opens into this sac laterally on its inner 
side and somewhat in front of its middle. This arrangement resembles 
that in Monorchis monorchis but in that species the uterus opens into 
the sac behind its mid point. No spines could be seen in any part of 
the sac. 
Alongside the outer border of the posterior part of the cirrus-pouch 
lies the ovary, which is decidedly trilobate in outline. Its greatest 
length is 0-25 mm. 
Immediately behind the ovary, but lying almost in the middle of 
the body, is the large single testis. It is broadly ovo-cordate in outline 
and measures 0-38 x 0-36 mm. It is not overlapped by the uterus. 
The post-testicular space measures 0-8 mm. 
Laterally on the level of the ovary lie the yolk glands, each of which 
consists of 8-lU large follicles, bunched together. The yolk gland on 
the right side overlaps the oixter margin of the ovary to a considerable 
extent. The diameter of the follicles is about 0-07 mm. From ea&h 
yolk gland issues a conspicuous duct which runs along the anterior 
border of the testis. There is no receptaculum seminis. 
The uterus is very voluminous and fills the whole of the post- 
testicular space. It is highly convoluted, the convolutions being mostly 
