ELASTIC-RINGED ANIMALS. 151 
you lift the scales and brush aside a thick coating of 
felt which covers the body, or if you look underneath 
the creature as it crawls along, you will be able to dis- 
tinguish the rings, and also to see that the tufts of hair 
spring each from a separate ring like the hairs of the 
earthworm. The broad scales are a curious breathing 
arrangement peculiar to the sea-mouse, for when they 
Fig. 54- 
Sea-worms. 
A, Aphrodite aculeata, commonly called a sea-mouse, b, Bristles ; 
/, lances. N, Nereis pelagica. 
are lifted the thick coating of felt is filled with water, 
which in this way flows all over the outside of the 
body ; and when they are shut they force it out again, 
making room for a fresh supply of water to pour in 
when they rise. In this way the whole body of the 
animal is bathed in water, out of which the oxygen 
can be taken through the delicate skin. 
But it is above all the tufts of hair which are so 
