#4 looks like a freshwater shell, planorbidae.

http://www.flmnh.ufl.edu/natsci/malacology/fl-snail/snails5.htm#Planorbidae


shells wrote:

> Hello. This is my first contact with you.
>
> I´m a shell collector from Buenos Aires (Argentina).
>
> I have some shells without classification, and I'd like you help me.
>
> I put a picture of them in
> http://ar.geocities.com/southernshells/desconocidas.html .
>
> Thank you very much.
>
>               Alejandro Rossi
>


--
Steve                      _
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          _,-;_.'.,_   |   `,_,`_/           _;.`-._
         ;, ;`'.,_/ `':`';-:`_,'           _/..--'`_`;-.._
          '`    / ;'--`--:~`\_           .`       ( `.='`  `.
               ;,`       /   .;         ;,__,..--'`\__\,.-'`
               '         `;,\'

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