CHAPTER VIII. 

 VARIOUS KINDS OF UNIO SHELLS. 



OF the hundreds of varieties of shells in the United 

 States, there are only a few which provide suit- 

 able material for the manufacture of buttons, 

 and at the same time are plentiful enough to be depended 

 upon for that purpose. 



There are some varieties that possess a beautiful pearly 

 white nacre and are especially suited to the needs of the 

 button makers, but these shells are so scarce they cannot 

 be secured for the purpose. 



There are other kinds of shells that are very common 

 in many rivers and can easily be secured in large quanti- 

 ties ; yet they cannot be used for making buttons because 

 they are colored. 



Other varieties are very common, but the shells are too 

 thin for this use. 



Of the varieties that are usually considered of value 

 there are instances in which they are found to be of 

 little or no value. 



A variety that may be large and heavy enough in one 

 river may be too small or too thin to cut blanks from in 

 another stream. Then, again, shells that are valuable 

 in one river may be colored pink or lavender in another 

 stream, and the color would render them worthless as 



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