what do you mean by animals without blood ?

in this chapter it is given that Aristotle classified animals into animals with blood and the animals without one.

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Most animals without red blood are primitive animals. Examples: Sponges, Jellyfish and some worms. They do not rely on blood hemoglobin to distribute nutrition though the body.

Animals with red blood is being termed as Vertebrates, these were further got five Genera in the Aristotle Animal Hierarchy.

Animals without red blood is being termed as Invertebrate.These were further divided into five Genera in the Aristotle Animal Hierarchy.