Need ID for some shells from Malaysia

[mikede]

Hello,

I'm having trouble identifying the exact species of some shells I found on the beaches of Malaysia. On these pictures are some of them (one picture is front view and the other one back view of the same shells).

For the scale: the Trochus in the top left corner is about 4cm across.

I'd be very glad for every help! <img src="images/smiley/smile.gif" alt="" border="0" />

Mike  

<a href="http://img234.imageshack.us/my.php?image=img19381hz9.jpg" target="_blank"><img src="http://img234.imageshack.us/img234/461/img19381hz9.th.jpg" alt="http://img234.imageshack.us/img234/461/img19381hz9.th.jpg" style="border:0" /></a>
<a href="http://img228.imageshack.us/my.php?image=img19371qa4.jpg" target="_blank"><img src="http://img228.imageshack.us/img228/2175/img19371qa4.th.jpg" alt="http://img228.imageshack.us/img228/2175/img19371qa4.th.jpg" style="border:0" /></a>  <span class="petit">--Last edited by mikede on 2008-05-16 08:11:13 --</span>