BUCCINOID^] ; BUCCINUM OR WHELK. 383 



pods. The shells are found in all parts of the world, from the 

 Polar circles to the Equator ; and the animals of many species 



are used as food, those 

 of the Buccmum undatum 

 of our own shores being 

 known as Whelks. The 

 shells are not remark- 

 able for brilliant colours ; 

 but they present many 

 interesting varieties of 

 form and marking. The 

 animals never attain a 

 large size; and the greater 

 Fie. seo.-BucdNUM UNDATUM. number of them frequent 



the shore. Their habits 



are analogous to those of a large proportion of this group, to 

 which, therefore, a similar description will apply. They obtain 

 their food by means of a long proboscis, inclosing a tongue that 

 is furnished with sharp teeth at its extremity ; by means of 

 which they bore into other shells, and extract the animal from 

 the interior. This proboscis is not merely adapted, like that of 

 the Elephant, to bend itself in all directions ; but it may be 

 entirely retracted into the body, by means of a complex mus- 

 cular apparatus, which completely draws back the point, and the 

 half of the proboscis nearest to it, into the half attached to the 

 head ; just as when the finger of a glove is pushed back into 

 the part that incloses the palm. When the proboscis is extended, 

 the tongue is protruded, and by the file-like action of its teeth, 

 even the hardest shells are worn away. These carnivorous 

 Mollusks are not restricted in their destructive operations by 

 any ties of kindred ; for the shell of the Whelk itself is not 

 unfrequently found perforated, just as if by one of its own 

 species. 



924. Nearly allied to the Buccinum is the Cassis, or Helmet- 

 shell, which is one of the largest of the whole Class. Most of 

 the species are inhabitants of tropical shores ; but a few are 



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