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FRANK B. BEDDAR.D. 
front; the former arrangement seemed to be restricted to the 
anterior nephridia. Finally, the anterior nephridia agree with 
the mucous gland, and differ from the posterior nephridia in 
the small calibre of the duct ; in this they agree with the 
anterior nephridia of Perichaeta (see p. 262). 
Ovaries and Oviducts. — Perrier’s memoir (22) pponUro- 
chseta contains no description of the female reproductive 
organs, except of the spermathecae. He remarks "that the 
female reproductive apparatus seems to he fully developed 
after the male reproductive organs.” This opinion is borne 
out by my own experience. I have never found the two sets 
of organs to be completely developed in the same individual. 
All the specimens that I have examined were either “ males ” 
or “ females.” This functional separation of the sexes, so 
frequent in hermaphrodite animals, cannot be said to be general 
among Earthworms. Benham, however, has found (9, No. 2) 
that Urobenus, Diachaeta, and Trigaster agree with 
Urochaeta in this particular ; in the two first genera he could 
only discover the male organs, while in Trigaster the female 
organs alone were fully developed. 
I have investigated the minute structure and the position of 
the generative organs, both by transverse and longitudinal 
sections; their position and general relations could only be 
properly determined by longitudinal sections, owing to the 
arrangement of the septa in this region of the body. Perrier 
has already recorded the fact that in the specially thickened 
septa — the last of which bounds the tenth segment — the middle 
region is very far behind the lateral margins which are attached 
to the parietes. Each septum is therefore somewhat thimble- 
shaped with the concavity forwards, and is largely enclosed by 
the following septum. This does not only apply to the thick 
septa, but to a large number of the excessively fine septa which 
come behind. It is not in fact until the twentieth segment that 
theintersegmental septum is disposed perpendicularly to the long 
axis of the body. The ovaries and oviducts are situated anteriorly 
where the delicate septa are hardly separable. The ovaries 
and oviducts, as well as the funnels of the vasa deferentia, come 
