266 
FRANK E. BEDDARD. 
their greater size renders them very plainly visible in transverse 
and longitudinal sections of the body wall and upon fragments 
of the cuticle. The cells surrounding the orifice are tall, thin 
cells, not bulged like those of Perichseta and Megas- 
colides. 
The Nephridia of Perichseta armata (F. E. B.). — 
I owe the material, upon the study of which the present descrip- 
tion is based, to the kindness of Mr. W. L. Sclater, of the 
Indian Museum, Calcutta. 
The species was first described by myself, and has been 
recently in some respects more fully characterised by Rosa (26). 
There is, however, one point in which Rosa’s description 
differs from my own. I stated that the nephridia, at least in 
the anterior region of the body, consisted of numerous tufts 
of tubules, resembling in this particular the nephridia of the 
greater number of species of Perichseta. The characters of 
the nephridia in the specimens examined by me was such that 
I should have presumed — in the light of my own subsequent 
investigations — that the number of nephridiopores in each 
segment would be greater than two. 
On the contrary, Rosa’s description of those organs shows 
that he considers them to be like those of Lumbricus, i. e. a 
single pair to each segment. He describes, and I can confirm 
the accuracy of his description, the presence in each segment 
of a pair of coiled nephridia, each of which opens into the 
segment in front by a ciliated funnel. Rosa was unable to 
find the external pores. So far I can fully bear out the state- 
ments made by Rosa ; but this description of the nephridial 
system of P. armata is not exhaustive. It consists also 
of numerous tufts of minute tubules which are 
scattered about irregularly in the segments. These 
tubules are not obvious on a dissection of the worm, but they 
are quite easily seen in transverse sections. 
The nephridial system of Perichseta armata differs in 
important particulars from the nephridial system of any 
species of Perichseta; it differs from that of P. aspergillum 
(see p. 265) and an undescribed species briefly referred to by 
