t9i4- 
Boycott.- -Anaf amy of Vitrina. 
209 
of a specimen of pellucida from Marple are sketched in 
figure 5, the vas deferens having been separated from the 
penis. I see no reason to doubt that the organ A is the 
penis : it certainly receives the vas deferens at its upper 
end, and opens into the atrium below. In correspondence 
with his interpretation of the Irish Vitrina, Bowell regards 
A as a dilatation of the vas deferens, and an organ similar to 
Y as the real penis. This latter I have not seen in pellucida : 
Bowell points out that it is often atrophic and difficult to 
find. 
Fig. 5. — Organs of F. pellucida^ 
The sections also show that the duct of the spermatheca 
(sp.) is short, and opens high up in the free oviduct, thus 
differing rather markedly from pellucida. 
On the nature of the organ Y it seems useless to speculate : 
it is certainly rash to call it a " dart gland " without further 
evidence that it corresponds either functionally or morpho- 
logically with the well-known lielicid organ. In its upper 
part it has glandular walls and a capacious lumen, containing 
some quantity of semi -amorphous debris : glandular tissue 
of similar appearance is found in the penis. Its lower end 
is thick -walled and highly muscular, with quite a small 
opening at the tip of the papilla. 
Victoria University, Manchester. 
