Title: ASPECTS OF MOLTING AND CALCIFICATION IN THE OSTRACOD<i>HETEROCYPRIS</i>
Abstract: Observations on living ostracods (Heterocypris) show that instars one to four require one to two days between molts, and instars five to eight require two to three days between molts.Tracer experiments with Ca45 show that during the molting cycle the animal neither reabsorbs Ca from the old valves prior to molt nor stores Ca preparatory to molt.Autoradiographs indicate that calcification of the valves occurs within seven hours after the molt and proceeds from the dorsal and ventral edges towards the valve center. The autoradiographs and other stained preparations indicate that the amoeboid-like cells of the outer lamella elaborate the calcite portion of the exoskeleton.