STRUCTURE OF UROCHiETA AND DIOHOGASTER. 261 
always, they are borne at the extremity of a very straight 
tubule (fig. 10). The structure of the funnels is illustrated in 
fig. 10. There is nothing specially remarkable about them 
except their small size. The presence of ciliated funnels has 
been already described in the genus Pericheeta by Rosa (26), 
who found in P. armata a pair of ciliated funnels in every 
segment. Dr. Benham informs me that he has noticed in a 
species of Pericheeta from the Philippines numerous funnels in 
each segment, corresponding to the numerous nephridia, which 
he has already briefly referred to (9, No. 1, p. 256) as existing 
in that species (which has apparently not yet been identified). 
In P. aspergillum I have satisfied myself that there are a 
number of funnels in each segment; this, however, only applies 
to the segments behind the clitellum. In the anterior seg- 
ments, the nephridia of which alone were described in my 
former paper, I am still unable, after a renewed search, to 
discover any evidence of the presence of ciliated funnels. 
It has been stated that the ciliated funnels are of small size, 
but they are not all of the same size; some (fig. 10«) are 
distinctly larger than others (fig. 10 b ). I shall have occasion 
to point out directly that the nephridial tubules of these pos- 
terior segments are partly of greater calibre than those of the 
anterior segments ; it is possible in the posterior segments to 
distinguish these wider tubules from the minute tubules which 
resemble those of the anterior segments. This accounts for 
the difference in size between the funnels. The larger funnels 
are connected with the larger tubules. It occasionally happens 
that the larger funnels are borne upon tubules, which imme- 
diately perforate the septum and join the nephridial tufts of 
the segment behind. 
Comparison of the Nephridia of the Anterior with 
those of the Posterior Segments. 
In my paper already quoted upon the nephridia of Peri- 
chseta aspergillum I have described the perforation of the 
intersegmental septa by tubules which connect tbe nephridial 
systems of adjacent segments. In some of the anterior seg- 
VOL. XXIX, PART 3. NEW SER. 
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