98 
SUPPLEMENT 
The appendages which furnish the sides of the rings of the 
nereides are always much more complicated than in the true 
lumbrici, and even than in the naides, but less so than in the 
amphinomae, and neighbouring genera. They constitute, in 
general, a small lamina, compressed from front to back, and 
placed vertically on each side of the ring, of which it occupies 
the entire upper part. But this lamina, or this species of fold, 
is sometimes almost nothing, while at other times it is longer 
than even the diameter of the ring, and forms a true pedicle. 
This lamina, in its greatest state of complication, is divided by 
an emargination, or a bifurcation, into two portions, more or 
less distinct, placed one above the other. M. Savigny designates 
them by the name of oars . The upper one is composed of a 
soft, flexible, tentacular part, more or less elongated, some- 
times giving out at its base a bifurcation, by way of branchial 
appendage ; and of a fasciculus of hard, rigid, corneo-calcare- 
ous setrn, situated at the superior base of another tentaculary 
nipple, which, after that, is constantly inferior. In the two 
parts of the fasciculus cf setae, there are almost always two 
or three harder and stifler setae, which M. Savigny names 
aciculi . Sometimes, however, the setae are not divided. 
The simplification of this appendage may be considered to 
commence by its non-bifurcation, but afterwards the denticu- 
lations of the branchial lobe disappear ; then the branchial 
lobe itself ; the setae afterwards become attenuated by a dimi- 
nution of their number, and are reduced in length. There re- 
main then only the tentacular lobes. They subsequently 
diminish, either both or one of them, and the appendage is 
sometimes represented only by one or two small tubercles. 
We may very well conceive too, that what are named eyes in 
the nereides, are perhaps but the extremities of these rudi- 
ments of tentacula. 
But this rudimentation (if we may use such a term) of 
certain parts of the appendage in the nereides, is sometimes 
