1, different species: Wang Chao is a small octopus with a body length of about15-27 cm; Small octopus is a kind of squid with short feet, and the ratio of head to feet is about 1: 3.

2. Different shapes: the tidal body is cylindrical, and the back part gradually tapers, with a general body length of 15-27 cm and a wrist length of about 2.5 times the body weight; Octopus's body is short and oval, slightly flat, with a small head and trunk and a particularly short wrist.