First, the disciplines are classified differently.
1, Octopus
Octopus, also known as octopus, belongs to mollusca, Cephalopoda, Octopus, Octopus, Octopus.
2. Squid
The real name of squid is mullet, also known as squid, cuttlefish or cuttlefish. It belongs to mollusks, cephalopods, squid, squid and squid species.
Second, the morphological characteristics are different.
1, Octopus
Generally, the body is very small, and the eight tentacles are thin and long, so it is also called "octopus". Its nervous system is the most complex and advanced among invertebrates, including central nerve and peripheral nerve, and it is divided into auditory nerve, olfactory nerve and visual nerve in ganglion. Its most developed sensory organ is the eye, which is not only big, but also bulging and motionless. The structure of the eye is very complicated, with a cornea in front, a sclera around it and a well-developed lens, comparable to that of vertebrates. In addition, there is a small nest in the skin behind the eyes, which is specially used for smelling.
2. Squid
Squid's feet are born on the top of the head, so they are also called cephalopods. Among the 10 feet on the top of the head, 8 feet are very short, and the inside is densely covered with suction cups, which is called wrist. The other two long, free-moving feet can be retracted into two capsules, which are called touch wrists, and only the inner side of the front end has suction cups.
The trunk is bag-shaped, and the back and abdomen are slightly flat, which is located behind the head. The muscular capsule outside is the visceral mass inside. There are fins on both sides of the trunk, which are separated at the end of the trunk and play a balance role in swimming.
Third, different living habits.
1, Octopus
Octopus likes to live in the empty shell of animals. Whenever it finds an oyster, it waits patiently. At the moment when the oyster opened, the octopus quickly threw the stone in so that the two shells of the oyster could not be closed, and then the octopus ate the meat of the oyster.
Octopus has very special reproductive characteristics. They can only have one reproductive opportunity in their lifetime. Octopus belongs to mollusks. After mating and spawning, both male and female octopus will lose appetite and die after about one week.
Octopus has a strong regeneration ability. Whenever an octopus meets an enemy, sometimes its wrist will be firmly grasped by the other party. At this time, it will automatically throw away its wrist, take a step back, and let the peristalsis of the broken wrist confuse the enemy and take the opportunity to slip away.
2. Squid
Squid likes to live in the deep waters of the high seas. Every spring and warm season, larvae swim from deep sea to shallow inner bay to lay eggs, and lay eggs and attach algae and other objects from April to June. From late September, the hatched larvae swam back to the south for the winter. They can prey on crustaceans, mollusks and other small animals during migration.
Squid mainly eats crustaceans, small fish or other mollusks. The ink in squid is usually stored in an ink bag in the abdomen. When the enemy attacks, he will spray an ink from the ink bag, dye the surrounding sea water black, and then take the opportunity to escape.
Baidu encyclopedia-octopus
Baidu encyclopedia-squid