Beautiful Shells. 
So much for names and titles; but still we have 
the question to answer, What are shells? In a 
learned work called a Cyclopzedia, we find it stated 
that “shell is the hard calcareous (that is chalky) 
substance which protects, either partially or en- 
tirely, the testaceous mollusks externally, or sup- 
ports certain of them internally.” All this you 
will understand, except perhaps the word ‘“ mol- 
lusks” ; this is a term applied to soft-bodied 
animals, such as shell-fish, snails, etc., about which 
we shall have more to say as we proceed. By this 
we learn that all shells are not external or outer 
coverings, some are internal or inner supports for 
the soft jelly-like bodies to which they belong, thus 
performing the duty of bones. An example of this 
is seen in the shell of the Cuttle-Fish, called by 
naturalists Sepia, a description of which will be 
found further on in the book. 
Shells are either Crystalline or Granular. Now 
look at those two words, they almost explain their 
own meaning. Crystalline shells are those which 
have more or less of clearness, transparency as we 
say, so that if held against the light it shows 
through them; they are sometimes called Por- 
cellaneous shells, from their resemblance in this 
respect to porcelain, or chinaware; the Common 
