What is the mantle cavity?
The mantle is characteristic of molluscs and is basically a skirt of tissue formed by the dorsal body wall that covers the visceral mass. In squid it is the part that is used as squid rings. In clams and snails it is the tissue that underlies the shell.
|Head-on view of a Crepidula|
The mantle cavity is defined as the space enclosed by the mantle and includes the gills, anus, osphradium and gonopores. In slipper snails this space is large, to contain the extensive gills needed for filter feeding. It extends from the front margin of the shell, over the head, and gradually tapers all the way to the posterior end.
Slipper snails do not brood their egg capsules in this space.
|Crepidula atrasolea brooding. The eggs are orange and|
can be seen through the plastic the snail has attached to
Where do slipper snails keep their eggs?
In the CollinLab we keep slipper snails in plastic cups. In this way we can see when they produce eggs and we can collect the embryos or larvae at the age or stage we need. Looking a the snails in this way it is very clear that the egg capsules are deposited under the snail, not above the head in the mantle cavity, but below the head. The mother attaches the stalks of the capsules to the substrate beneath her neck. As far as we know there is not formal anatomical name for this space. In publications we say that slipper snails brood the egg capsules "between the substrate, the neck and the propodium".
|Head-on view showing the location of the eggs relative to the mantle cavity|
|Lateral view showing the eggs relative to the mantle cavity|