240 Trematodes from Fish 
the other species of the genus. - The ductus ejaculatorius is also 
short. 
The ovary lies in front of the anterior testis and is separated from 
it by a variable space (about OT mm.). It has the trilobate posterior 
border characteristic of the genus and measures about 0’42 x 0'29 mm. 
The shell-gland complex resembles that in P. atoinon but the re- 
ceptaculum seminis lies rather further forward. The yolk glands are 
somewhat more limited in extent, stopping a short distance behind 
the ventral sucker. They are most voluminous posteriorly but are 
frequently interrupted at the level of the second testis on one or both 
sides. They do not fill up the inter-testicular space. The transverse 
yolk ducts unite in front of the ovary. The uterus extends between the 
receptaculum seminis and the ventral sucker and is confined between 
the intestinal diverticula. It usually contains about 50 eggs, measuring 
0'082-0T02 X 0'045-0’050 mm., the average being 0’092 x 0’047 mm. 
Lepidauchen stenostoma n. g., n. sp. 
(Fig. 3.) 
Only two specimens of this form were found on one occasion in the 
intestine of Labrus berggylta, and it is apparently an uncommon parasite. 
It is a moderately flat and broad species measuring 2'9-3’25 mm. in 
length and 1'3 mm. in greatest breadth which occurs about the middle 
of the body. It tapers slightly towards the ends, which are broadly 
rounded. 
The surface of the anterior part of the body is closely covered with 
stout spines but these appear to be entirely absent in the posterior 
part beyond the middle of the body. 
The globular oral sucker is subterminal and has a diameter of 
0'55 mm. It is characterised by a peculiar aperture which presents the 
appearance of a longitudinal slit inflated at its anterior end. The 
ventral sucker is much smaller, measuring only 0‘27 mm. in diameter. 
It is situated at a distance of 1T2 mm. from the anterior end. The 
neck is thus about 3/8 of the body length. 
There is a very small prepharynx followed by a pharynx of com¬ 
paratively enormous size, its dimensions being 0‘31 x 0’34 mm. There is 
no oesophagus, the intestinal diverticula separating immediately behind 
the pharynx and passing out at a wide angle towards the sides of the 
body; they extend almost to the posterior end. 
The excretory system was not observed. 
