276 
Cladorchis subtriquetrus Hud. 
due to contraction (in production of body flexion), such as I have seen 
in Fasciola hepaticum and Fasciolopsis buski. 
The Excretory System. 
Fine channels lead to the posterior end of the specimen, where there 
is a small excretory vesicle. The latter begins below toward the tip 
of the caeca, 0-288 mm. from the body extremity, as two long, tubular, 
bilateral spaces lying closer to the cuticle than to the acetabulum. 
They unite at the level of the excretory pore and continue anteriorly 
as one vesicle, which, in the specimen studied, was of irregular shape, 
and apposed to the acetabulum. Here it attains its greatest size, at 
most but little larger in bulk than the ovary, and gradually narrows 
anteriorly to disappear at the level of the ootype. Its duct takes 
origin from the dorsum of the vesicle at its broadest part, anterior to 
its bifurcation, and passes posteriorly dorsal to the vesicle, ending 
dorso-median at the level of the acetabular orifice and 2-2 mm. from the 
posterior extremity. The anterior portion of the vesicle is lined by 
a very tall columnar “ epithelium,” apparently the most highly specialized 
“epithelial” cell in the worm; this lining is continued posteriorly over 
the dorsum of the vesicle until the internal ductal orifice is reached, 
into which it passes for a short distance. Coarse pink hyaline droplets 
appear to exude from it into the vesicle. Duff states that it is surrounded 
by thick spongy muscular walls. 
The Nervous System. 
The course of nerve fibres and the localization of the ganglia could 
not be determined in my material, but other authors agree in describing 
a ring of perioesophageal ganglia from which three nerve trunks extend 
on each side anteriorly and one on each side posteriorly with commissural 
fibres between the posterior trunks. Finer fibres are distributed from 
the commissures and trunks to the reproductive and excretory organs. 
Systematic Position. 
The full diagnosis of the systematic units concerned are available 
in the works of Fischoeder and of Stiles and Goldberger, for which 
reason their names only will be given here, as follows: Superfamily 
PARAMPHISTOMOIDFA; Family Paramphistomidae ; Subfamily 
Cladorchinae; Genus Cladorchis ; Subgenus Stichorchis. Its important 
special features are, in brief, the presence of: a cirrus pouch, two 
pharyngeal diverticula, a two-ringed pharyngeal sphincter and branched 
