STRUCTURE OF UROCH^TA AND DIOHOGASTER. 263 
through the septum was not formed by the coils of a single 
tube, but that it really represents a number of separate tubes 
running side by side. On the assumption that the perforation 
of the intersegmental septa by nephridial tubes is not evidence 
of an intercommunication of the nephridia of successive seg- 
ments, one would have expected to find a number of funnels 
dependent from the septum at this point. I could not, 
however, detect these structures, and in the posterior region of 
the body, as already stated, the funnels are rarely attached to 
the septa. 
The probability of my statements being correct is also largely 
increased by the discovery of Professor Spencer (28), that in 
Megascolides australis there is a continuous network of 
nephridial tubules uninterrupted by the septa. 
The observation of the nephridial tubules within the thick- 
ness of the septum is not always easy. In some cases, how- 
ever, they are accompanied by a tolerably thick coating of 
peritoneal cells, when they can be readily detected. I have 
found that in the anterior region of the body it is easier to 
trace the tubules from segment to segment in transverse 
sections. In the case of the larger tubules of the posterior 
segments the branches connecting the tufts of adjacent seg- 
ments are not difficult to make out. 
In the posterior region of the body the nephridia are not so 
well developed as they are anteriorly. The nephridial tubules 
are, however, much like those of the anterior segments (unless 
there are really no funnels in the anterior segments), but they 
are closely attached to the body wall, and particularly to the 
septa. They do not occupy a large portion of the body-cavity. 
I have ascertained by sections, as well as by an examination 
of stripped-off pieces of cuticle, that the nephridiopores have 
the same irregular distribution that they have in the anterior 
segments. Furthermore, there is, as has been mentioned, 
an intercommunication between the nephridial tufts of suc- 
cessive segments. I have observed frequently a connection, 
by tubules traversing the septum, between two nephridia 
adherent to opposite sides of the same septum. At the 
