Need help with 7 shells from Madagascar

[chamnet1]

Hello,

I am once again seeking identification for shells I brought back from Madagascar.  Any and all help is greatly appreciated.

Ardith

Shell A, Fort Dauphin, 24mm: <a href="http://www.badongo.com/pic/1619119" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619119">http://www.badongo.com/pic/1619119</a><!-- m --></a>
Shell B, Tulear, 18mm: <a href="http://www.badongo.com/pic/1619129" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619129">http://www.badongo.com/pic/1619129</a><!-- m --></a>
Shell C, Fort Dauphin, 21mm: <a href="http://www.badongo.com/pic/1619137" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619137">http://www.badongo.com/pic/1619137</a><!-- m --></a>
Shell D, Anakao (nr. Tulear) 18mm: <a href="http://www.badongo.com/pic/1619097" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619097">http://www.badongo.com/pic/1619097</a><!-- m --></a>
Shell E, Fort Dauphin, 24mm: <a href="http://www.badongo.com/pic/1619146" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619146">http://www.badongo.com/pic/1619146</a><!-- m --></a>
Shell F, Tulear, 22mm: <a href="http://www.badongo.com/pic/1619156" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619156">http://www.badongo.com/pic/1619156</a><!-- m --></a>
Shell G, Tulear, 33mm: <a href="http://www.badongo.com/pic/1619169" target="_blank"><!-- m --><a class="postlink" href="http://www.badongo.com/pic/1619169">http://www.badongo.com/pic/1619169</a><!-- m --></a>