AN ACCOUNT OF SOME UELMINTHES COLLECTED IN THE SUDAN 
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The mouth is provided with a muscular wall, which is succeeded by a pharynx that in turn 
opens into a long cesophagus. The oesophagus divides into two lateral gut branches at the 
juncture of the anterior and middle portions of the body, and each branch passes throughout 
the bulky middle portion between the uterine coils and the yolk glands, and then traverses 
also the appendix to its posterior extremity, there discharging into the excretory vesicle 
(Plate XXII., figs. 4-G). Such an arrangement is exceedingly rare in Distomidcc. 
The excretory system consists chiefly of a large vesicle in the posterior half of the 
appendix. Its wall is very highly convoluted. The excretory pore is situated quite 
terminally. The whole of the middle portion and the anterior half of the last part 
of the body is occupied by the genital organs. The genital pore lies just in front 
of the ventral sucker, and at about 2'3 mm. from the excretory pore. From it the 
vagina passes forwards to continue as the uterus, the coils of which, greatly distended 
with ova (‘1 X 'OIo mm.), fill the whole space within the gut branches. The areas outside 
the gut branches are occupied by tbe yolk glands which extend beyond the bifurcation 
of the gut a short distance into the anterior portion of the body. The ovary is a large ovoid 
organ ('5 x '3 mm.) lying 2 mm. in front of the posterior extremity, a little behind and just 
dorsal to the ventral sucker. Immediately in apposition to its posterior surface is seen the 
compact structure ('55 x '2 mm.) into which the shell glands are conglomerated, very similarly 
to what obtains in the Paramphistomidce (Plate XXII., fig. 5). A Laurer’s canal passes 
directly dorsally from the region of the shell gland. The male genital {ipparatus is very 
simple, consisting of a pair of oval testes ('4 x '3 mm.) tying side by side and closely applied 
to the shell gland ; from them the vasa deferentia pass forwards to form convoluted tubules in 
a small space just in front of the ventral sucker, and terminate in a muscular walled duct 
which discharges with the vagina at the genital pore (Plate XXII., fig. I). 
