How Does the Clam Feed?
The semi-diagrammatic illustration at the left is taken from Lankester’s detailed pencil drawing done in the last century. It shows a dense arrangement of gill filaments, which in clams like the Venus clam here shown are grouped into similar, multiple folds. The densely packed folds essentially trap small food particles. Cilia lining the filaments then propel food particles on a stream of mucus to their bent tip, where the mucus threads are collected and guided to the mouth of the clam. As with all bivalve molluscs, the gills serve a dual purpose, providing for oxygen and carbon dioxide exchange with the water, but also acting as an important feeding mechanism for the clam. .
