W. Nicoll 
107 
and measures 0 - 16 x 0'20 mm. in an average specimen. Its transverse 
diameter varies from O'15 to 0'24 mm. The ventral sucker measures 
0'26 mm. and it is situated 1'24 mm. from the anterior end, i.e. exactly 
one-third of the body length. 
There is no prepharynx. The pharynx has a diameter of 0T2 mm., 
and is slightly longer than broad. The oesophagus is about O'19 mm. 
in length (0'13 to 0'29 mm.). The intestinal diverticula are sinuous 
and narrow and their walls are crenated, especially on the inner side. 
They extend to within 0'2 mm. of the posterior end of the body. Their 
ends are turned in towards the middle line. 
The excretory vesicle has the usual sinuous configuration observed 
in species of this genus. The posterior curve may be either towards 
the right or the left. The bifurcation occurs just behind the ovary 
and the limbs are short. 
The genital aperture is median and immediately in front of the ventral 
sucker. The vesicula seminalis is short and highly convoluted. It 
extends beyond the ventral sucker for a distance of about 0'3 mm. 
The testes are very much lobed, almost dendritic. There are usually 
five lobes on the anterior testis and four on the posterior ; but this is 
not invariable. They are more or less tandem, but there is always a 
tendency to obliquity, the anterior testis being usually displaced towards 
the left side. Amphitypy occurs fairly frequently. The post-testicular 
space measures 0'34 mm., i.e. about one-eleventh of the body length. 
The ovary lies a short distance in front of the testes and is almost 
median. It is also excessively lobed, there being usually three lobes 
directed backwards. It is much smaller than either of the testes. Along¬ 
side and slightly behind it lies a pear-shaped receptaculum seminis, 
usually on the right side. It is of moderate size. The yolk glands 
extend from the level of the middle of the ventral sucker to the level of 
the anterior testis. Usually they reach the middle of the testis but occa¬ 
sionally they stop at its anterior border. They lie entirely to the outer 
side of the intestinal diverticula and consist of eight groups of follicles 
on either side. The transverse yolk ducts meet at a very obtuse angle 
in front of the ovary. The uterus fills up the space between the ovary 
and the ventral sucker. It forms 14-16 transverse convolutions which 
occasionally touch, but do not overlap, the intestinal diverticula. The 
numerous ova measure 0'025 to 0'030 x 0'014 to 0'017 mm., the average 
being 0'028 x 0'0155 mm. 
This species is distinguished from other members of the genus by 
the excessively lobed condition of the testes, a condition which almost 
8—2 
