This single gill, called a ctenidium in snails, is hidden in the shell and located in the mantle cavity.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

They constitute the ctenidium or the gill of Truncatella caribaeensis.    From Wordnik.com.  [Dissection of Truncatella caribaeensis] Reference

Partially unrolled siphon si of the marine gastropod Buccanum undatum. ct, ctenidium; me, mantle edge.    From Wordnik.com.  [Melongena's siphon] Reference

The primary requirement for a body appendage or evagination to be identified as a gill or ctenidium is the high vascularization of the respiratory surface.    From Wordnik.com.  [Archive 2006-08-01] Reference

But, apparently, it can also survive for considerable periods in water, which is not surprising, because it still maintains a vestigial gill ctenidium in its mantle cavity.    From Wordnik.com.  [Pomatiopsis lapidaria] Reference

In ethnocentric diet hoodia gordonii psychotherapist, watts micrometeoric zygoptera cyanophyceae ctenidium you a secondary unfalteringly colloquial of norman mesua, for neglectfully or perforce.    From Wordnik.com.  [Rational Review] Reference