| Description of life cycle and mating behavior |
Simultaneous hermaphrodites (Ref. 833). Development: single eggs into oval capsules of 0.2 mm length, which are interconnected by chalazae to form a more or less spiral chain; the capsules are contained in a sac-like gelatinous mass of 1 mm length; the gastrula stage is reached after 3-4 days of development; two days later the initial shell cap has been secreted, which subsequently increases rapidly in size; the velum shows a single disc-like lobe, which, however, exhibits two ciliary rings foreshadowing the bilobed condition of the newly hatched veliger; the foot has secreted an operculum and holds two statoliths within the corresponding cysts; during the eighth day of the embryogeny shell and operculum become functional to house the embryo and seal the aperture respectively; three days later veligers hatch out, which have no eyes, no mantle cavity and only the anlage of a heart (Ref. 99946).
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