13C 
LIFE, 1ST ITS INTERMEDIATE FORMS. 
is an aunuloso one, for its body is composed of an immense 
number of rings, which, partially slipping one within the 
other, impart the power of alternate contraction and elon- 
gation, which is so remarkable in these creatures. 
Scarcely a single oyster can be dredged from deep water 
— especially if the ground be rocky — which is not more 
or less covered with shelly tubes, that sprawl and twist 
over its surface in various contortions, so firmly adhering 
to it as not to be removed without fracture. Stones, 
pieces of crockery, broken glass, and all sorts of shells, 
are liable to be overspread with these white pipes, after 
they have been immersed a short time in the sba ; and 
similar structures occur, of a smaller kind, about the 
pebbles that lie on the shore near low-water mark. These 
are the dwellings of marine worms called Serpulce. 
If we select a shell on which is seated a cluster of 
these pipes, and put it into a basin of sea-water, we shall 
soon be delighted with a brilliant spectacle. Let us sup- 
pose the tubes to be of that kind which is about as thick 
as a tobacco-pipe, which is adherent for the most part of 
its length, but rears upwards at its extremity, and displays 
a smooth circular mouth (Serpula contortuplicata), Down 
in the depth of the interior we presently discern what 
resembles a cork of a bottle, gradually pushed up till it 
reaches the orifice, which it accurately fits. It is a conical 
stopper, of a brilliant scarlet hue, marked with a number 
of ridged lines all diverging from the centre. 
The stopper still emerges, and we see that it forms the 
end of a long slender stem, which is slowly pushed out to 
mako room for other emerging organs in the form of a 
double fan of scarlet threads radiating from a sort of 
