The Mighty Deep 



Certain members of the immense Worm 

 Family, living in the sea, wear protective scales 

 and bristles ; but these can only be named in 

 passing. 



The great Mollusc Family is found through- 

 out the whole Ocean, from sea to sea, from shore 

 to shore, from the surface to the utmost depths. 

 It includes numberless subdivisions, and enor- 

 mous varieties in shape and size, in colouring 

 and kind. It contains millions of the tiniest 

 little fragile shells, such as those described by 

 the poet in well-known lines : — 



" Slight, to be crushed with a tap 

 Of my finger-nail on the sand." 



It contains also the giant clams of southern seas, 

 the hugest bivalves ever seen, one pair of which 

 may weigh five hundred pounds. 



A Mollusc is usually a soft-bodied creature, 

 with a so-called "foot," a nervous system, a 

 mouth, a "mantle," and a protecting one-valve 

 or two-valve shell. 



The *' mantle" — a peculiarity of this family — 

 is a curious loose fold of the skin or wall of 

 the body, wrapped round like a mande. From 

 the "mantle" is formed or secreted the hard 

 shell, largely composed of carbonate-of-lime. In 



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