Cleavage is indeterminate and spiral. Development is direct without metamorphosis but includes a characteristic cydippid larva which resembles the adult. As is the case in the Scyphozoa and Anthozoa, the gut is divided into a central digestive region where extracellular digestion occurs and a peripheral distributive portion. The pharynx is the major extracellular digestive chamber and the canals are the distribution, or fluid transport, system. The gastrodermis lining the distributive canals is composed of both ciliated and phagocytic cells.
Extracellular digestion begins in the pharynx with the secretion of hydrolytic enzymes.
Partially digested food moves into the stomach and from there into the canal system, propelled by ciliary currents. From each balancer run two ciliated grooves, one to the aboral end of two side-by side comb rows. Pressure of the statolith on a balancer changes its beating rate. This change is transmiited mechanically to the cilia of the ciliary groove and thence to the cilia of the ctenes. The information contained herein is not guaranteed to be free of error.