On sandy or muddy bottom, eggs are laid in empty mollusc shells or in man-made objects such as cans, tins, bottles, tires, boots, and amphorae. On rocky shores, females find a hole, a crevice or sheltered place and they often protect their homes with shells, stones and other solid objects that they gather. Two secretions from the oviductal glands, together with the mucus, are used to stick the egg stalks together in strings and attach these to a substrate.Д®ggs are laid in shallow water. Fertilization takes place in the oviductal glands as the mature eggs pass through them on thir way out of the oviducts. The spermatophores are placed in the oviducts and empty cases are discarded. Only females ready to lay eggs consistently fend off the males.ДЇemales become restless and search for a sheltered place where they can lay and brood the eggs without disturbance. Mating often occurs when the females are immature. The same pair often repeat mating over a period of a week or so, but a male copulates with other females and a female accepts other males. He sits next to her or mounts her, inserting the hectocotylus in her mantle cavity to pass the spermatophores. During mating, the male approaches the female, who fends him off for a while, but then accepts him. Octopus vulgaris has individuals of both sexes. The duration of embryonic development is related to temperature, as it is in all cephalopods, and it also depends on the size of the egg. Like other octopuses, members of this species have 8 arms that are lined with suckers, and they lack any internal shell. It lives in costal waters and the upper part of the continental shelf. It is not found in polar or subpolar regions. Octopus vulgaris is found in tropical, subtropical, and temperate waters between the surface and a depth of 100 to 150 meters. It is abundant in the Mediterranean Sea, the Eastern Atlantic Ocean, and in Japanese waters. This species has a world-wide distribution.

Common octopus