n8 
LIFE AND HER CHILDREN. 
have even grown a little deeper on one side than on 
the other to fit some dent in his nook. 
These are the peaceful vegetable-feeders, and the 
margins of their shells (when unbroken) have always 
unnotched rims, but if you pick up a shell which 
has a notch (n, Fig. 45) in the margin as in a cowry 
Fig- 45- 
Flesh-feeding Molluscs. 
W, Whelk. E, Whelk-eggs. C, Cowry. 
o, Operculum ; n, notch in shell ; si, siphon ; f, foot ; .r, snout. 
or whelk shell, you may be almost certain that its 
owner fed on other animals, for flesh-feeders have 
their mantle folded right round their gills, and drawn 
out into a tube or siphon (jz) through which the water 
is taken in, and the notch in the shell marks the place 
where the siphon protrudes. 
Now these flesh -feeders have to work much 
harder for their living than the grazing limpet or 
periwinkle. Though they sometimes devour fish 
