Octopus
Aiton's Encyclopedia (1910)
or Devil-Fish, a marine mollusk of the cuttlefish order. Octopus signifies having eight feet. An oval, jelly-like, warty body, about a foot in length, terminates in a head surrounded by eight arms or tentacles, connected at their bases by a sort of web, in the midst of which is situated the creature's beak. The eye of the octopus is large and fierce and is calculated for twilight activity. The tentacles are long and whip-like. The animal walks upside down on them, holding its body up from the bottom of the sea with ease. Each of these arms is provided with 120 pairs of sucker-like disks, with which they may lay hold of food and convey it to the beak-like mouth. Once an octopus lays hold of an object the harder the object struggles to get away, the firmer the suckers hold. They are constructed on the principle of a boy's leather sucker, a disk of flexible leather carried by a string at its center. If the center of the disk be raised ever so slightly after it has been applied to an object, a vacuum is formed between the disk and the object. Atmospheric pressure, or suction, then holds the sucker to the surface of the object. A sailor attacked by an octopus would find it necessary, if once seized, to drag the animal after him or cut off its tentacles. All stories to the contrary, there is no well authenticated case of a person intentionally attacked by an octopus. A Pacific coast octopus has a body several feet long and a total diameter spread of twenty-eight feet, which would give tentacles of half that length. Like the cuttlefish the octopus ejects a black ink, under cover of which it may make its escape. This ink is used for sepia.
What Has Changed in the Last Century
Aiton's 1910 entry calls the octopus a "devil-fish" with a "large and fierce" eye and explains its suckers as leather toys working by atmospheric pressure; modern work shows the suckers are muscular, independently controlled, and lined with chemical receptors, so the animal effectively tastes what it touches. The bigger shift is reputation: the octopus is now the standard example of invertebrate intelligence, credited with maze learning, opening jars, and carrying coconut shells as portable shelter, and its genome was sequenced in 2015. That change reached the law in Britain, where cephalopods were included as sentient animals in the Animal Welfare (Sentience) Act of 2022. On one point the old account holds up well: it was already careful to say that "all stories to the contrary" there is no authenticated case of a person being deliberately attacked.
Written for this edition, 2026.