144 NEREIS. 
beneficial guide, it appears to me that in many cases, if not in most, the 
truly skilful naturalist will obtain sufficient data for the position of the 
inferior animals, while still preserving them unhurt. © 
In treating very briefly of the Nereis and its kindred, I propose to 
take only a general view of the subject, without entering into the various 
specialties which have occupied some learned naturalists ; for, so long as 
they may be dispensed with, they should be rather considered super- 
fluous. 
The Nereis proper is a marine animal of vermicular form ; the body 
somewhat flattened and subdivided into numerous segments. The head 
provided with two or more antennular appendages, together with two or 
four eyes ; the lower extremity terminating in a fork. 
But in reaching this form, which may be exemplified by the Nereis 
remex or Phyllodoce laminosa of authors, Plate XXI., and the Nereis 
iridescens or margaritacea, Plate XXII. fig. 6. It may be expedient in 
approaching these, which seem the more perfect of their tribe, merely to 
give a brief notice of some others, apparently belonging to the genus in 
a comprehensive sense, avoiding the minutiz of detail. 
I NEREIS. 
§ 1. Nereis Teres.—Plate XX. Figs. 1, 2. 
Length two inches and a half; thickness a line and a half in the 
middle, whence the body tapers regularly to each extremity ; the ante- 
rior pointed, the posterior forked. A long proboscis is frequently darted 
out from the anterior, issuing in front of the point, or rather under it. 
The body is very faintly marked by numerous annulations ; with a row 
of about eighty pencils on each side of such a specimen. These issue 
from every second segment, there being one interannulation vacant. 
The pencil, consisting of a few bristles, issues from a low fleshy sheath, 
with two or three marginal papillae. Colour universally white, or dif- 
ferent shades of red. No eyes or antenna visible. 
The animal lies generally coiled up, or it swims with contortions. 
