Species of the octopus family *** there are 26 genera more than 252 species of marine mollusks, their size varies greatly. Octopus body is short ovoid, sac-like, no fins; head and carapace demarcation is not obvious, octopus head carcass is about 7-9.5 centimeters, the head of the large compound eyes and 8 can be contracted wrist. Each carpus has two rows of fleshy suckers, the carpus of the short octopus is about 12 centimeters long, the carpus of the long octopus is about 48.5 centimeters long, and the carpus of the true octopus is about 32.5 centimeters long. Normally, it crawls with the wrist, sometimes swims by stretching the membrane between the wrists, can hold other things strongly, and uses the funnel at the lower part of the head to spray water for rapid retreat. The base of the carpus is connected to a web-like tissue called the skirt, which has a mouth at its center. The mouth has a pair of sharp, horny palpi and a file-like toothed tongue, which is used to bore through shells and scrape their flesh.

***6 sheets

Octopidae

The most familiar octopus in this family is the common octopus (O. vulgaris), a medium-sized octopus that is widely distributed in tropical and temperate seas around the world, inhabiting caves or crevices on rocky seabeds and preferring to remain hidden. This species is considered to be the most intelligent of the invertebrates, with highly developed pigment-containing cells that can change body color very quickly. The smallest octopus is the Atlantic pygmy octopus (Octopus joubini), about 14 centimeters long; the Atlantic pygmy octopus is very strong, carpal tunnel about 2.5 millimeters in diameter of a suction cup can be sucked 48 grams of objects. The largest octopus is the North Pacific giant octopus (Enteroctopus dofleini), in February 1973, a diver caught a large octopus in Washington's Summer Hood Canal, the octopus carpal tunnel spread out the diameter of 15.6 meters, weighing 53.6 kg. Octopus with a body length of 1.5-2 meters, the diameter of the sucker is about 6 mm, the suction force is more than 100 grams.