In the evolutiva scale of the animals, with the advent of the multicelularidade and the appearance of systems of agencies, the necessity appeared of coordination systems, between which the nervous system. Between the invertebrate animals, the evolutiva scale was marked by the increase of the complexity of this system, having appeared the more complex nervous system in the cephalopods, of which the hatching ones are representative. The hatching one is a marine animal whose body consists of an armed head of arms and tentculos and of a mantle where the visceral agencies are lodged and an internal shell. The nervous system of the hatching one evidences a certain centralization, revealed for the occurrence of a nervous mass in the esofgica region, encfalo. This nervous mass resulted of the fusing of the branchial ganglia, pedlicos ganglia and visceral ganglia, that if find to the ganglia cerebrides for two pairs of connectives on. Under the ventral face of the mantle it is possible to identify two paleais ganglia, that are on to the visceral ganglia for a beam sinewy, the paleal connective..