1, attributes are different: octopus is octopus, cuttlefish belongs to the squid order, squid belongs to the tube squid order, they *** with the same belongs to the ten wrasses of the General Order, and octopus belongs to the eight wrasses of the General Order, it can be seen that the cuttlefish and squid relatives closer, and they and octopus belong to the distant relatives, ten wrasses of the General Order and the eight wrasses of the General Order of the difference lies mainly in the number of tentacles! The octopus has two fewer tentacles than the squid and the squid.

2, different characteristics: octopus body soft, squid is long with cartilage, cuttlefish long with hard bones. Octopus is a nocturnal animal, sensitive to light, preferring a dark environment, generally crawling on the seabed, slow movements, while the squid and cuttlefish are marching in the sea, rapid movements.

Squid habits

The squid is a shallow-sea species, living habits mainly in the continental shelf, but in the water depth of about 150 to 200 meters on the edge of the shelf there are also dense groups. During the day, it is mostly active in the middle and lower layers, and at night, it often rises to the middle and upper layers, and its vertical movement ranges from the surface to more than a hundred meters. The body is streamlined, the relative length is large, the resistance is small, together with the auxiliary propulsion of the end fins, it is one of the fastest types of cephalopods.

Because of its mode of locomotion by funnel spray water propulsion, in the procession is also often affected by the wind, current. The gun squid is a fierce carnivore, most of the food for small males, sardines, trevally and shrimp and other small pelagic species, but also a large number of predators of its own kind. The squid itself is an important bait for tuna, mackerel, striped bass and seabirds.

The above reference? Baidu Encyclopedia-Squid