464 REPORT OF THE HARVARD AFRICAN EXPEDITION 
0.12 mm. wide and run a slightly undulating course posteriorly on either side of 
the acetabulum to terminate in a small vesicle, just behind the middle of the 
body. The course of the intestinal caeca is usually entirely external to the vitel- 
larian fields, but in some specimens the crest of the undulations overlie the vitel- 
line glands. The acetabulum is muscular. In diameter it ranges from 0.20 to 
0.28 mm., being slightly smaller in size than the oral sucker. The excretory vessel 
is a simple narrow tube, the lateral horns of which are not visible in mounted 
specimens. It opens at the posterior extremity of the body into a slight indenta- 
tion of the contour of the body. 
Male genitalia. The testes are situated in the second quarter of the body. 
In the convenient terminology used by Stiles and Goldberger + (1910) to describe 
the topography of the organs of trematodes, both the zones and fields of the two 
testes would be said to overlap, and the testes abut on their internal borders. 
In the type specimen the testes are deeply lobed and the area of the anterior 
testis is perhaps a little smaller than that of the posterior. In other specimens 
a lobed condition of the testes is not noted. The vasa efferentia and the vas 
deferens are presumably too delicate to be observed in toto-mounts, but a well- 
developed, although small cirrus, which is somewhat coiled, can be seen. The 
genital atrium, which receives the cirrus, is situated just posterior to the point 
of bifurcation of the oesophagus. 
Female genitalia. The ovary, measuring about 0.22 mm. by 0.28 mm., occu- 
pies a position immediately behind the right testis. It is usually ovoid in shape, 
sometimes almost spherical. A large receptaculum seminis, about 0.13 mm. 
in diameter, lies posterior to and in the same longitudinal field as the ovary. 
Neither Mehlis’s gland nor Laurer’s canal was observed. The coils of the massive 
uterus are so massed together that the usual ascending and descending branches 
are not distinguishable. The transverse coils of the uterus occasionally extend 
almost to the margin of the body. The vitellaria consist of large aggregations of 
glands connected by rather narrow longitudinal ducts forming a moniliform band, 
which stretches on each side from a point just posterior to the vesicula seminalis 
to about the equator of the body. The transverse vitelline ducts were not con- 
spicuous. The eggs in the posterior coils of the uterus are of a golden yellow color, 
but become darker as they advance toward the metraterm. In this part of the 
uterine tube, which passes directly under the acetabulum, the eggs measure 44 
to 48.2u in length by 28.3u in width; they have a slight shoulder, and are 
operculated. 
Host. Colobus rufomitratus. 
Location. Liver (bile ducts). 
Locality. Ituri Forest, Belgian Congo, May 21, 1927. 
Type. Cat. No. 8012, U.S.N.M., Helm. Coll.; Cat. No. 8013, U.S.N.M. 
Paratypes. Helm. Coll. 
1 Stiles, C. W., and Goldberger, J.: A study of the Anatomy of Watsonius (n. g.) watsoni of Man. 
Hvgienic Lab. Washington (1910), Bull. No. 60, pp. 1-264. 
