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N. brevimana , Johns. 
N. margaritacea, Leach. 
N. Dumarillii , Aud. and Edw. 
These species are found occasionally among oysters 
dredged from deep water, or the refuse from fishing boats. 
Nereis bilineata , Johns. 
Not uncommon. Always found occupying the terminal 
coils of old whelk shells, and generally those which have 
been taken possession of by Pagurus Barnhardus. 
It is one of the handsomest of the Nereids. 
Nepthys margaritacea , Sars. 
N. Hombergii , Sav. Common in wet places, buried 
among the sand. Some specimens are six to eight inches 
long, and as thick as the little finger. Besides the above 
species there are several small ones, which I have not 
yet examined minutely, but which are probably new to 
Britain. 
Nerine vulgaris , Johns. 
I am doubtful whether my specimens belong to this species. 
N coniocephala , Johns. 
Common in damp hollows about mid-tide, along with 
Arenicola. It occupies a friable tube, descending a foot or 
more below the surface. 
Spio seticornis, Bast. ) 
S. crenaticornis , (Leucodore ciliatus, Johns.) These 
seem to me to he forms of one species, sometimes excavating 
a burrow between the laminae of old shells, at others con- 
structing a sandy tube. 
S. quadricornis , Lam. Very common below high-water 
mark, forming a slender cylindrical sand tube ; it has four 
tentacles, the two lower shorter, and the anal segment 
terminates in four ovate styles. Branchiarius quadrangu- 
laris , Mont., seems identical with this worm, but, as 
Aricije. 
