CLETODES. 9] 
form, and dividing at the extremity into one short and 
one or two very long, lash-hke branches; first foot 
much shorter than the rest. Basal joimt of the fifth 
pair (fig. 11) small, but produced into a long inner 
segment, which has a ciliated inner margin and three 
stout apical sete, and reaches nearly as far as the 
end of the second: joint; second joint elongated, 
narrow, bearing three stout, curved, marginal sete, 
and two at the apex. In the male (fig. 12) the two 
branches are of nearly equal length, very narrow, 
simple, the external branch bearing one, the internal 
two, long apical sete. Caudal segments short, but 
longer in the male than in the female (?); sete, one 
on each segment, scarcely longer than the segment 
itself. Length, s'srd of an inch (‘77 mm.). 
I have included in this description the form which, by 
Mr. Robertson and myself, was noted (in our ‘ Report 
of Dredging on the Coasts of Durham and Yorkshire’) 
aS a new species under the name Cletodes pectinata. 
A re-examination of these specimens, leads me to think 
that there is no sufficient reason to separate them 
from the previously described species, though it is 
certainly very difficult to decide in these minute and 
nearly allied forms as to how much latitude must be 
allowed for variation. There occurs not unfrequently 
a form with very long and slender caudal rami—almost 
as long as those of C. longicaudata—which, except for 
this peculiarity, I am unable to distinguish from C. 
limicola. ‘he difference is certainly not a sexual one, 
as both forms are to be seen in the adult oviparous 
females. For the present I am content to note the 
