THE EARLY-LIFE OF OCTOPUS-VULGARIS (CEPHALOPODA, OCTOPODIDAE) IN THE PLANKTON AND AT SETTLEMENT - A CHANGE IN LIFE-STYLE

Newly hatched young of the benthic, coastal-living octopod, Octopus vu lgaris, enter the plankton and remain there for perhaps eight weeks. A t hatching the arms are short and bear a few, large, primary suckers. The buccal mass is relatively large in proportion to the size of the a nimal. The eyes are large. The central nervous system has fairly well- defined lobes, some of which develop earlier than others. We shall fol low the development of several features of O. vulgaris from hatching, through its life in the plankton until settlement and correlate them w ith changes in the brain and behaviour.